Hey guys. I just picked up this '05 that I'll be building as a project car for Modified Mag (which I work for). The plan is to build it as a STX legal machine and take it to the Nationals. I haven't done much autocrossing the last four or five years (mostly been road racing and doing some Time Attack events), but I used to be a very active cone dodger back in the day and I'm looking forward to getting back into it (though I'm sure I'll get my ass handed to me at the Nats...I'll be there so I can produce a good story for the mag and hopefully not embarrass myself too badly in competition). I'll also take it to some lapping days, maybe a Time Attack or two, and will be track testing all the mods made in a step by step fashion so I can document how the car's performance has improved throughout the project.

http://i259.photobucket.com/albums/hh314/Modified_Dave/RX8.jpg

My first STX legal mods have arrived already and I'm looking forward to bolting them up tomorrow.

http://i259.photobucket.com/albums/hh314/Modified_Dave/G2_5.jpg
http://i259.photobucket.com/albums/hh314/Modified_Dave/G2_3.jpg

The rims weight 19 lbs, which is among the lightest on the market in a 18x9. I've used RE-11s on a C6 Corvette with good success for Time Attack, so it'll be interesting to see how they work on the 8 for autox.

Got some other good stuff ready to be installed too, but any advice or feedback you guys might have about how to go about building a competitive STX class 8 would be greatly appreciated. Long-term I may look to do a custom Rotrex supercharger install or maybe some kind of engine swap, but for this year the plan is to max out the build as much as possible within the STX rules.

Nice to see Modified taking on an RX8... with the cost of used ones getting so low it's only a matter of time before a ton of them are being modified.

nice, I'll be following this

Good luck with this project! I look forward to seeing your progress with the car.

Good luck with the build!

name everything you put on the car, price aswell would be nice and what you get from it... woudl be highly appreciated.. i'll follow the thread to the end...

name everything you put on the car, price aswell would be nice and what you get from it... woudl be highly appreciated.. i'll follow the thread to the end...

Same, id like to follow the thread to the end as well. I always love seeing people progress, and from the sounds of it yours will be one story to follow.

I love the rims!!!!

It is great seeing an 8 written up. With a 35 offset and wider wheels and tires, will you have rubbing? I have 30 offset wheels that are 18X8 and the current tires are only 235 and they look very close to the outer fender with -2 camber.

So far I have KW3s, track pads and Rcomps for running road courses. I found a Mazsport cooling mod which will be needed both for traffic jams and track days when temps go up.

Please let us know how much you drop it and if you see any bad geometry changes. I have read here that if you drop the front more than and inch it starts creating problems.

Where are you located?

I love those rims man, I was looking at those yesterday!

*scribed to thread

+1 to modified for takin' on the 8.


another +1 for listing of mods and places they were purchased

PLEASE.. PLEASE confirm with us specific parts you use before you write up a "How to".. Its been the norm to pick up the mag and read an article listing a build path that has so many poor decisions listed among it that it would throw many people for a loop, especially on a vehicle like the RX8 which is still rather uncommon in the tuner community.

Welcome to the class.

Just FYI, if the rule changed proposed in the March Fastrack (http://cms.scca.com/documents/Fastrack/10/10-fastrack-march.pdf) goes into effect, you will have to pull that Mazdaspeed front bumper and go back to stock. The proposal is out for comment right now.

same for the rear wing rule, and given the general thought process coming from the SEB/STAC lately it will likely go through. I really want to install one, but hate to dump the dough for one seasons worth of use. Really glad I didn't import that Fabulous body kit from Japan. :uhh:




.

Thanks for the great response, guys! I'm really excited to build this car and I have to say in stock form (well, almost stock) it's a lot more fun to drive than my previous project, a '06 G35 coupe. I've always been a fan of lightweight, nimble feeling, high revving cars so the 8 pushes all the right buttons for me.

TeamRX8, I'm in the Toronto area. I'll be working the bugs out at local autox events up here, plus I plan to attend 1 or 2 SCCA events in the northeast prior to the Nats. I don't think I have a racing resume online anywhere but here's a little bio from my personal website:

http://www.tune2win.com/index.php/about/david_pratte/

I guess my highlights from behind the wheel would be the 2005 Canadian SoloSprint (what we call Time Attack up here) overall and T1 class championships as well as six race wins in the Canadian Touring Car Championship. I've also done the 25 Hours of Thunderhill three times now, last time in a factory-backed Mazda MX-5. I also consider driving the Nurburgring last summer a real highlight. That place is the epicenter of motorsports culture in so many ways.

Anyway, here's the price list so far:

2005 Mazda RX-8 w/ 66k km (about 40k miles), cloth interior, no sunroof, Mazdaspeed CAI (which I'll be removing since it's not STX legal), front strut tower bar and front bumper. Everything else is stock. Oh wait, I spotted a Racing Beat rad screen too so it may have the RB oil cooler screens as well. I'll have to check on that. $12,000

18x9 Volk Racing G2 wheels. I bought these direct from Mackin Industries at a discount, but street pricing on these ain't cheap...about $2800. To be honest I wanted to go with a less expensive wheel because I think a Solo 2 build should be done on a reasonable budget (but of course everybody's definition of "reasonable" is different), but if I was going to blow the budget anywhere it was going to be on wheels since nothing changes the look of a car more. I personally really like the look of the G2's but I know they're not for everyone. This Lambo was kind of my inspiration in terms of color scheme:

http://www.bespokeventures.com/blog/wp-content/uploads/2009/08/0026-wallpaper21.jpg

265/35-18 Bridgestone RE-11s sell for $282/each on TireRack.com (I got my direct from Bridgestone), so about $1200 mounted and balanced. Not the cheapest STX tire choice, but having used these before I'm a fan of their at-the-limit characteristics so that's why I opted for them on this build. Not sure how well they'll work in a autox setting, but only one way to find out. Might order a set of Kumho XS and Toyo R1R to do an autox comparo. What do you guys think of this idea?

For suspension, I just received a set of BC Racing BR-RA coilovers with 8 kg/mm front and 5 kg/mm rear spring rates. They're standard rates are 8k front and 6k rear but I opted to soften the rear up a bit after looking at other STX RX-8 builds including some of yours (thank you rx8club.com). Hopefully I can get the balance I want with this spring rate setup along with an adjustable front anti-sway bar (thinking Mazdaspeed). Anyway, I have never used BC Racing coilovers before, but they've been an advertiser with the mag long enough that I felt I should give their product a try. My G35 was on KW Variant 3's which I liked a lot and my Honda Civic race car is on Moton triple adjustables but those would have blown the budget even worse than the VR.G2's :) Anyway, pricing on the BC coilovers is very reasonable at $1250 so we'll see how they stand up to some track testing and autox use. I plan to put them on a shock dyno to see how they're valved and how they respond across their full range of damping adjustment.

The only other mods I have in my possession a this point is a ARK MFD ($349 MSRP) so I can monitor oil temp, oil pressure and water temp. Will probably mount it where the ashtray is since I'm not a smoker. I also plan to order a Cobb AP of course, along with some bolt-on power adders (most likely from Racing Beat, including a STX legal ReVi intake without the duct or maybe I can modify the duct so that I don't have to remove that rad shroud that renders most CAI's illegal for the class). Still trying to sort out my options in terms of the exhaust system since I want a very livable sound quality to go along with the best power gains possible (don't we all?). Also still looking at other suspension details like bushings, sway bars, alignment, etc. Will definitely corner balance the car and may put it through a full suspension geometry analysis to see if we need to fab up some roll center adjusters or bump steer adjusters once we lower the car (assuming these types of adjusters are STX legal...anybody know off-hand?). I won't be lowering it too aggressively though, since I need the car to remain a practical daily driver. I like the way a "hellaflush" car looks, but I'm a racer first and foremost and I know from experience that going too low is a no-no in terms of suspension travel and geometry.

Still learning lots about the car and motor every day. Haven't decided on what oil to run nor have I figured out what trans or diff fluid to run, if a LSD upgrade to a clutch-type 1.5-way is worthwhile, etc.

Sorry for the long post and certainly appreciate any feedback you guys might have!

EDIT: interesting deal about the Mazdaspeed aero bits. Hope that rule doesn't go through since I love the way the MS bumper (and planned side skirts) look! Ah well, I guess I can always swap a stock bumper on for autox events and go back to the MS bumper for track days and street driving.

sLaPcHoP edit: Oh, I should also mention I do have some Hawk pads for the car. Got a set of HP+ for the front and HPS for the rear. The HP+ might have a bit too much initial bite for some drivers, but I quite like them for street and autox duty, plus they should be able to handle the heat of some track testing and lapping/TA use. Will go up to a DTC-30 if the HP+ overheat at the track. Pricing on these from TireRack.com are $112 for the front HP+ and $71 for the rear HPS. Might look at doing a lightweight rotor and caliper setup to save some unsprung and rotating mass, but only if it can be done for reasonable money since the 8's brakes sure look to be big enough to handle the heat even at a brake-intensive test track like I use (Toronto Motorsports Park).

Have you seen here that someone has tapped into the display above the stereo/ventilation? They will display multiple readouts from OBD2 and hopefully will work out aux inputs for oil.

http://www.rx8club.com/showthread.php?t=195323

I think there is still a used Brembo big break kit in the For Sale section.
Edit: FS: Brembo Brake Kit (http://www.rx8club.com/showthread.php?t=196767&highlight=big+brake)

The tire comparo I would like to see would be: Hankook R-S3 vs. Dunlop Star Specs vs. RE-11

IIRC the AEM/Mazdaspeed intake can be modded to be STX legal.

ganseg, thanks for that link. Very interesting display that guy has developed, but I think for oil temp and oil pressure I'll still need to install sending units in which case I may as well link them to the ARK MFD since it's a pretty cool little display unit too. BTW, are the 02 sensors on the 8 narrowband or wideband? Just wondering how useful the afr data would be if pulled off the OEM sensors.

Solidtrance, thanks for the Brembo link. I'll have to do some research to see if that kit is lighter than the OE components.

I could certainly test the Hankooks and Dunlops instead of the Toyos and Kumhos if you guys think those are the more competitive STX options out there right now.

Sounds like I've got some searchin' to do on the AEM/Mazdaspeed intake mod to make it STX legal. Thanks for the tip.

. BTW, are the 02 sensors on the 8 narrowband or wideband? Just wondering how useful the afr data would be if pulled off the OEM sensors.


wideband - and quite accurate . Only issue is that it only reads down to 11.15 which the stock tune runs at a lot . If you get the AP that will all change and you can use the screen to readout AFR if you wish .....

Good luck with the build. Looks like you are off to a solid start.

Hi Dave,

Do you plan on showing up for any SoloSprint events this year? I believe my 8 is the only one competing this year.

Once you've done two racing events (i.e. Solo I or II, etc.) you are eligible to join the Mazda Motorsports program and get parts at cost. They also distribute all the Speed Source parts. You can also get a variety of brake pads including the Hawks at cheaper prices.

The Mazdaspeed front sway bar is not adjustable. Mazda Motorsports has an adjustable sway bar for over $500 but it is made by Speed Source. I inquired and they weren't sure if it would fit a stock car, possibly only good for the GT race cars. However, there are other adjustable options available.
I've used HP+ pads in the past and prefer stock over them but I currently use Mazdaspeed B-Spec pads which are even better IMHO. Note that the Mazdaspeed stuff is only available through dealers for customers in the USA.

Also, there is a thread on the Canada regional site for bringing Jeff (aka Mazdamaniac) up from the US to do a tuning day with the Cobb AP. He came up for a day a year or so ago for a tuning session at Splitfire in Brampton.

Regards,

SoloSprint #112

Welcome and I'll have to try to get a hold of some Modified mags for the write-ups.

Just FYI, if the rule changed proposed in the March Fastrack (http://cms.scca.com/documents/Fastrack/10/10-fastrack-march.pdf) goes into effect, you will have to pull that Mazdaspeed front bumper and go back to stock. The proposal is out for comment right now.
+1 I also have the feeling that the body kit allowance in the ST* category will go bye-bye after this season.
same for the rear wing rule, and given the general thought process coming from the SEB/STAC lately it will likely go through. I really want to install one, but hate to dump the dough for one seasons worth of use. Really glad I didn't import that Fabulous body kit from Japan. :uhh:
Agreed. One-season aero isn't worth the expense.
I like the way a "hellaflush" car looks, but I'm a racer first and foremost and I know from experience that going too low is a no-no in terms of suspension travel and geometry.
Ha ha. But the "hellaflush" look will turn heads! :lol:
I could certainly test the Hankooks and Dunlops instead of the Toyos and Kumhos if you guys think those are the more competitive STX options out there right now.
Hankooks and Dumlops have typically performed better on heavier cars than the Toyos. The Kumho XS's are a great choice for the dry, but even then they need a significant amount of heat in them before they work at their best. The Bridgestones and even the Yoks are good all around tires. I would love to see a test comapring the RE-11's, AD08's, RS-3's and Star Specs on your car.

Hi Dave, welcome to RX8Club & STX. Look forward to following the buildup.

As for the tire test, I'd rather see a 17" vs. 18" test, using the same tire, than another tire brand test. Frankly, swapping brands can lead to changes in balance, and unless you take some time to tweak your setup for each brand it may be difficult to get good data. I think having a good data point on the wheel size debate would be of particular interest to the RX-8 crowd, and would add meaningful data that is currently missing from our community.

So, my vote is to get some 17" RPF1s & 255/40-17 RE-11s and see what happens!

Hi Dave,

Do you plan on showing up for any SoloSprint events this year? I believe my 8 is the only one competing this year.

Once you've done two racing events (i.e. Solo I or II, etc.) you are eligible to join the Mazda Motorsports program and get parts at cost. They also distribute all the Speed Source parts. You can also get a variety of brake pads including the Hawks at cheaper prices.

The Mazdaspeed front sway bar is not adjustable. Mazda Motorsports has an adjustable sway bar for over $500 but it is made by Speed Source. I inquired and they weren't sure if it would fit a stock car, possibly only good for the GT race cars. However, there are other adjustable options available.
I've used HP+ pads in the past and prefer stock over them but I currently use Mazdaspeed B-Spec pads which are even better IMHO. Note that the Mazdaspeed stuff is only available through dealers for customers in the USA.

Also, there is a thread on the Canada regional site for bringing Jeff (aka Mazdamaniac) up from the US to do a tuning day with the Cobb AP. He came up for a day a year or so ago for a tuning session at Splitfire in Brampton.

Regards,

SoloSprint #112

Yup, I'll definitely be out for a weekend of SoloSprint with my 8. So you'll have some rotard company, at least for a couple events. Not sure what class the car will be in...that'll depend on where I am in the build process. With street tires and coilovers looks like it'd be in GT3 but if I do swaybars in time for whatever weekend I end up running at then it'd be in GT2.

I am planning to sign up with the Mazdaspeed motorsports program. They certainly have an unrivalled support and contingency program, not to mention their racing ladder development system. The cool thing about Mazda is that they're run by a bunch of true racing fanatics. At last year's 25 Hours of Thunderhill race there were a number of Mazda America's top execs who did stints in the same MX-5 that I drove.

On the Mazdaspeed site I noticed they've just recently listed an adjustable front sway bar, but maybe that's the GT-spec Speedsource bar. I'll have to look into that.

Interesting about Jeff from Mazdamaniacs coming up to Toronto. I was planning to have Sasha from SG-Motorsport tune the Cobb AP for me since he's done an amazing job on all my other cars. I know the Racing Beat guys quite well so was planning to have them guide Sasha's tuning since they know a thing or two about rotaries, but if Jeff is up here it'd be cool to work with him on this.

chiketkd, glad to hear I'll at least be able to run my MS front bumper this season. By next season the car may not be STX legal any more anyway, depending on how quickly the build progresses. By that time maybe it'll be a full-blown hellaflush show car! LOL. More likely it'll have a cage in it for Targa Newfoundland or something like that.

Interesting that the o2 sensors don't read below 11.15. How strange is that? Normally a wideband reads from 9.65:1 to 20:1. I'm amazed that Mazda has bothered reducing the range of its wideband sensors, but presumably there's some (emissions-related?) reason for it?

Thanks again for the warm welcome, guys! I hope to do the RX-8 community proud with the build and show the broader tuner/racing community what a great chassis the 8 has. I actually feel in love with this car when I drove AutoExe's demo car at Fuji Speedway a few years ago while over in Japan for the Tokyo Auto Salon. The sound of that car at 9k rpm and the amazingly well-balanced handling made it one of the quickest cars on the track despite being one of the least powerful. I had some nice big four-wheel drifts going through Turn 1 that the AutoExe guys were loving. LOL.

Hi Dave, welcome to RX8Club & STX. Look forward to following the buildup.

As for the tire test, I'd rather see a 17" vs. 18" test, using the same tire, than another tire brand test. Frankly, swapping brands can lead to changes in balance, and unless you take some time to tweak your setup for each brand it may be difficult to get good data. I think having a good data point on the wheel size debate would be of particular interest to the RX-8 crowd, and would add meaningful data that is currently missing from our community.

So, my vote is to get some 17" RPF1s & 255/40-17 RE-11s and see what happens!

+1
I second this :)

good luck, i will enjoy the progress

+1
I second this :)
+2 I would be happy to see this as well!

Nice, I read Modified from time to time. Nice to see the 8 get some love outside of a un drivable show car.

+2 I would be happy to see this as well!

I figured I'd get that kind of reaction. Although, to be fair, a brand test would have broader appeal to the magazine's reader base, while a 17 vs. 18 test would be very specific to the RX-8. We can always hope, though!

sLaPcHoP edit: Oh, I should also mention I do have some Hawk pads for the car. Got a set of HP+ for the front and HPS for the rear. The HP+ might have a bit too much initial bite for some drivers, but I quite like them for street and autox duty, plus they should be able to handle the heat of some track testing and lapping/TA use. Will go up to a DTC-30 if the HP+ overheat at the track. ...
Welcome to the club! I'm looking forward to seeing the finished ride.

The stock brakes on the RX-8 are exceptional. I've been unable to fade the HP+ pads in the two years I've been using them on my RX-8. The tracks include VIR Full and Grand East, Summit Point main and Shenandoah. Just finished a weekend on the Shen. I've kept a set of Blues in the parts bin since I first got the car, but haven't needed them yet. Your skill level is certainly higher than mine, but I don't think you'll be disappointed with the HP+.

Wankelbolt, good to know I shouldn't be concerned about brake fade with the HP+. The test track I use is ridiculously hard on brakes, so if I don't get fade there then I won't get it anywhere (why does this sound like the New York, New York song? Haha).

Guys, I think the idea of a 17'' vs 18'' wheel/tire setup is brilliant. Love it! I'll definitely set this up. I actually have a buddy with a set of 17x9'' Enkei RPF1's, so all I'll need is the tires and I'm pretty sure Bridgestone will take care of me on that since it'll be a doubly good story for them in the mag. I'm going to try to make this happen!

^Sweet! It would be great if you could do things like -

- Make sure both sets have roughly the same tread depth when the test is undertaken. The RE-11s have a tread pattern that puts progressively more rubber on the ground as they wear.

- Take a little time to try & determine an optimum pressure for both. Given the shorter sidewall, the 18" might like a bit lower pressures.

- Get some good accelerometer data from the runs so that we can see if the tires excel at different areas of the solo course. Ultimately, it's the final time that matters, of course, but the more detail the better.

Apologies if this is all obvious.

Wankelbolt, good to know I shouldn't be concerned about brake fade with the HP+. The test track I use is ridiculously hard on brakes, so if I don't get fade there then I won't get it anywhere (why does this sound like the New York, New York song? Haha).

Guys, I think the idea of a 17'' vs 18'' wheel/tire setup is brilliant. Love it! I'll definitely set this up. I actually have a buddy with a set of 17x9'' Enkei RPF1's, so all I'll need is the tires and I'm pretty sure Bridgestone will take care of me on that since it'll be a doubly good story for them in the mag. I'm going to try to make this happen!

OoOooOoOh - i would definitely be interested in reading that if it provided all the details and differences.

Subscibed!

^Sweet! It would be great if you could do things like -

- Make sure both sets have roughly the same tread depth when the test is undertaken. The RE-11s have a tread pattern that puts progressively more rubber on the ground as they wear.

- Take a little time to try & determine an optimum pressure for both. Given the shorter sidewall, the 18" might like a bit lower pressures.

- Get some good accelerometer data from the runs so that we can see if the tires excel at different areas of the solo course. Ultimately, it's the final time that matters, of course, but the more detail the better.

Apologies if this is all obvious.

I appreciate the input, George. Never assume a magazine guy has thought things through :p

I use a Driftbox for all my in-car data acquisition (both GPS and accelerometer based data) and I'll definitely take tire temps across the contact patch to see if/how my starting pressures and alignment need to be tweaked for optimum grip. With racing slicks and DOT r-compound tires you want about 20 degrees more temp on the inside third of the contact patch than on the outer third (eg. 180, 190, 200 F from outside to inside), but for autox I'm guessing this will be very difficult to achieve. Plus street tires do provide close to their maximum grip at lower operating temps, but your thoughts on a target temperature range would be appreciated.

I was thinking about shaving my RE-11's to about 5/32nds for max dry grip, but since I was planning to use these as my daily street tires I think I'll leave them at full depth and do the same with a set of 255/50-17's. Then what I might do is get a fresh set shaved for the Nationals if I'm really focused on optimizing the setup for the big show. Problem is, if I optimize my setup to the nth degree and still get my ass handed to me, I won't have a built-in excuse :suspect:

Here's a couple stories I did on my G35, just to give you some idea of the type of data I'll be collecting while building the 8:

http://blog.stillen.com/wp-content/gallery/misc/ModifiedMag1108_APRacing.pdf

http://www.modified.com/tech/modp-1002-project-2006-infiniti-g35-wrap-up/power-gains.html

and do the same with a set of 255/50-17's.
Probably a typo, but just in case it wasn't... ;)

The correct 17" size you want to order is 255/40-17

^lol - good catch! those would be some beefy sidewalls :lol:

your thoughts on a target temperature range would be appreciated.

Dave -

I don't have that info right now. I intended to ask the guys in the Bridgestone truck at the Wendover NT yesterday, but I never got around to it. Hopefully they will be at the Pro this weekend. I'll see what I can learn, and I'll also ask about the ideal temp distribution. I do know getting a realistic temp distribution across the tire can be tough in a typical solo scenario, given the hard braking that is usually necessary at the end of a run.

I will say that the RE-11s can overheat, especially in a two-driver scenario in warmer conditions. Easy to manage with spraying.

Anyway, based on my experience thus far, I'd say their optimum operating temps are much lower than you list above. If the tire feels hot when I place my hand on the tread after a run, I spray. Not very scientific but that's where I'm at right now.

Probably a typo, but just in case it wasn't... ;)

The correct 17" size you want to order is 255/40-17

LOL...yeah, a 255/50-17 would work nicely on a SUV though!

thanks for sharing Dave, subscribing

I'm taking the 8 for its maiden voyage at Toronto Motorsports Park this evening to baseline it and test the new wheel/tire combo vs the OEM wheels and tires (actually, the tires on the OE rims are Toyo T1R's in the OE size). I'll let you guys know how it goes.

Anyway, in preparation for the track I swapped on the Hawk pads last night and decided to weight the OEM wheel/tire combo to see how heavy it is compared to the new VR.G2's and Bridgestones. I was pretty impressed to see that I've only gained about 1.5 lbs even though rim width and tire width has increased substantially with the new setup.

http://i259.photobucket.com/albums/hh314/Modified_Dave/RX8brakes.jpg
http://i259.photobucket.com/albums/hh314/Modified_Dave/OErollerweight1.jpg
http://i259.photobucket.com/albums/hh314/Modified_Dave/OErollerweight2.jpg
http://i259.photobucket.com/albums/hh314/Modified_Dave/Newrollerweight1.jpg
http://i259.photobucket.com/albums/hh314/Modified_Dave/Newrollerweight2.jpg

Not sure how accurate my bathroom scale really is, but presumably the difference between the two is fairly accurate. Anyway, thought you guys might find this interesting.

nice

Welcome Dave!

Look forward to the progress of the vehicle if you need anything let me know. If you are looking into some light weight brake upgrades I would suggest looking at what Racing Brake has to offer.

http://www.racingbrake.com/v/main/vehicle/mazda.asp?model=RX-8

They have Two Piece Rotors and Lightweight Calipers so they have tons of different options. If you are interested in pursuing that route I am sure I can work something out.

If you have a questions about a specific direction in which to take the car, just ask. There are tons of sources within the community to help.

Enjoy, this should be an excellent read once it is done.

While that SRF brake fluid doesn't hurt, personally I think it's overkill. I run Castrol LMA in my 8 and Spec RX-7 and have never managed to boil it.

Take some video inside and outside the car! Never enough RX-8 track videos!

Bed those pads tonight! You don't want to get green fade into wall.

i wanna follow this

Are you planning to test the car at any track days at Mosport (Kensai, 6th Gear, Apex, etc)?

Let us know what track days / Solo 1 events you will attend, a few folk from the Toronto area may come out to check out the car and your progress.

What kind of alignment settings are you planning?


Subscribed to the thread.

My car has -2 degrees of camber all around with a mild drop. Still eat up the outside edge of the front left tire at a track with predominently right turns and high speed (NT01s 245/40 on stock wheels). Don't have enough miles on my street tires to say for sure, but I think the -2 with 0 toe is fine wear wise.

Race Roots, thanks very much for the generous offer. I'll be in touch about the lightweight rotors from Racing Brakes.

wankelbolt, I agree on the SRF. It's expensive and overkill on a project like this, but I happen to have a box full of the stuff from a sponsorship deal on my racecar so I figured I might as well put in the good stuff. This way I won't be bleeding brakes often if at all. Normally I like Elf Frelub 650 in my street/track cars since it's worked very well for me and costs 1/4 as much as SRF. I've also had good performance out of Motul RBF600 but it's twice the price of the Elf stuff.

burglar, don't worry dude, I broke the pads in before going to the track and let them fully cool. I used to be a Hawk distributor back in the early 2000's. I learned my pad brake-in lessons many moons ago :) The brakes performed extremely well at the track tonight, btw. No fade to speak of, which really impressed me since TMP is absolutely brutal on the brakes. Two thumbs up to Mazda for the brakes on this car!!!

Chris_Bangle, I'll probably be at one or two Kensai days at the big track, though to be honest I'm always a bit uneasy about putting a street car on that track. I've seen too many cars go home on a flatbed there to want to push my street car beyond 9/10ths around that track. Anyway, I'll let you know what track days I'm at, just in case you want to come out for some fun. I'll be at TMP pretty often, testing the car every time we upgrade something on it. Will probably do the coilovers next, so I'll let you know when that's going to happen.

For alignment settings, that'll be determined by the tire temperature data and how the car feels to me at the limit, but as a starting point I'll likely go with something like -3 degrees of camber up front along with a bit of toe out (maybe 1/16th on each front wheel, so total toe out of 1/8th) and -2 degrees of camber in the rear along with zero toe or maybe a smidge of toe-in depending the swaybars I go with. That may be a bit less rear camber than some guys like, but I tend to set my cars up for maximum front grip and a little bit of understeer at the limit, so my rear tire temps don't generally indicate I need more rear camber.

Speaking of tire temp data, we collected some good data on the Bridgestones tonight, so I'll post that up once I get a chance. But the quicky version is the rear of the car seems to gain more camber than the front and appears to have more static camber than the front as well, and the tire temp showed this to be the case too. In terms of lap times, the car went 3.5-seconds a lap quicker (best time of 1:25.8) on the Bridgestones than on the OE sized Toyo T1R's (best time of 1:29.3). The Mazda is already as quick as my G35 was with KW coilovers and AP big brakes. I think I'm going to like the 8 -- a lot :)

Oh, also gotta thank my friend Will Chan from Enmo Racing (who recently won their class at One Lap of America and finished 8th overall in a twincharged EG Civic!) who collected all the tire data for me tonight. It's good to have friends who are SAE engineers :)

Do you have a way to know how the camber is changing up front? I have read not to lower it more than an inch, which is what i did. I'd like to get more camber too but -2 is all I got with the 1"drop and a track alignment (he pryed them out further than just turning the camber bolt to the max position). I would love to know if I can drop the front more without screwing up the geometry,

Dave -

You may want to take a look at - RX8 Racing Lower Control Arm Bushings made by MazdaSpeed from MazdaTrix:

http://www.mazdatrix.com/8susp1.htm

Listed in the middle of the page. While I am not an expert they may help with the front alignment settings.

Keep us posted on the event.

Welcome Dave,

I look foward to following your thread. Good luck bro....

Dave -

You may want to take a look at - RX8 Racing Lower Control Arm Bushings made by MazdaSpeed from MazdaTrix:

http://www.mazdatrix.com/8susp1.htm

Listed in the middle of the page. While I am not an expert they may help with the front alignment settings.

Keep us posted on the event.

Chris, spherical bearings aren't STX legal so I can't run those lower control arm bushings. I could run their Delrin front upper replacement bushings though, I think.

Anyway, here's a few pics and some data from the track test last night. I was pretty happy to get the car down into the 1:25's after starting out in the 1:29's. The upgraded wheel and tire package made a world of difference. As you can see, we were working the outsides of the front tires pretty hard (understeer) but using more of the middle and inside of the rear tire (sliding the car a bit on corner exit to get rid of some of the understeer). FYI, TMP is a clockwise track that puts an especially hard beating on the left side tires, especially the left front. We didn't touch the alignment at all, just tried to get the tires working as best we could with the stock alignment for this test. Once I put the coilovers on we'll really try to dial in the alignment settings for optimum tire temps across each contact patch.

Oh, and before you guys rag on me about the lack of a helmet, I always, Always, ALWAYS wear a helmet at the track (and usually wear my full safety gear including nomex head sock, suit, gloves, socks and shoes) but like a rotard without the ro part I left my duffle bag full of race gear on the garage floor. My driftbox was in there too, so we just made do with what Will had handy, meaning a Longacre pyrometer and Hot Lap timer and a tire pressure gauge. We were kickin' it like it was 1999! Anyway, please don't be a dumbass like me. Always wear a helmet at the track!

http://i259.photobucket.com/albums/hh314/Modified_Dave/RE11data.jpg
http://i259.photobucket.com/albums/hh314/Modified_Dave/RE11test1.jpg
http://i259.photobucket.com/albums/hh314/Modified_Dave/REtest4.jpg
http://i259.photobucket.com/albums/hh314/Modified_Dave/RE11test2.jpg
http://i259.photobucket.com/albums/hh314/Modified_Dave/REtest3.jpg

No video this time, but will definitely take video next time.

I had another racer (in this case autocross) tell me today not to drop the front lower than 1". he also said that an RX-8 doesn't need as much camber as like my E36 M3. I ran -3.4 degrees on that at the track. He's thinking -2.5 would be good on an RX-8 (I know -2 is still too little for track). Thanks for the dialog - this is fun!

I had another racer (in this case autocross) tell me today not to drop the front lower than 1". he also said that an RX-8 doesn't need as much camber as like my E36 M3. I ran -3.4 degrees on that at the track. He's thinking -2.5 would be good on an RX-8 (I know -2 is still too little for track). Thanks for the dialog - this is fun!

I assume this recommendation comes from concerns over bump steer? It's easy to measure bump steer if you have the right tools (my friends at Auto Analyser Racing have a jig that mounts to the hub and you then stroke the suspension through its full range of travel and dial gauges show you how much toe change is occurring. You then shim the tie rods to greatly reduce toe change and therefore eliminate bump steer, since bump steer is simply toe change that occurs while travelling over a bump).

However, I'm not sure if bump steer correction is permitted in STX. I see in Section 14.8 A of the 2010 rulebook that roll center adjusters aren't permitted, where the rule reads "This does not allow the use of spacers that alter suspension geometry, such as those between the hub carrier and lower suspension arm." I also see in 14.8 F that shimming the steering rack isn't permitted, but I wouldn't be shimming the rack, I'd be shimming the tie rod end. But maybe the tie rod end is considered part of the steering rack? Does anyone know the SCCA's position on bump steer correction by shimming the tie rod ends? Is it STX legal?

Anyway, I will do a bump steer analysis of the 8 using AAR's jig so that I can at least see how bad the bump steer gets as we reduce the car's ride height.

Anyway, I will do a bump steer analysis of the 8 using AAR's jig so that I can at least see how bad the bump steer gets as we reduce the car's ride height.

Whoo hoo!

Dave, I'm pretty sure that because there is no rule that specifically says something like "tie rod ends may be relocated to alleviate bump steer," you can't do it. The bit about prohibiting shimming of the steering rack is just to clarify the steering rack bushing allowance.

I'd still love to see your bump steer curves though! Front and rear would be awesome.

Also, great thread!

Dave, I'm pretty sure that because there is no rule that specifically says something like "tie rod ends may be relocated to alleviate bump steer," you can't do it. The bit about prohibiting shimming of the steering rack is just to clarify the steering rack bushing allowance.

I'd still love to see your bump steer curves though! Front and rear would be awesome.

Also, great thread!

Yeah, I think you're probably right Kenneth, but maybe I should shoot the SCCA an e-mail just to be sure. Woud be sweet if I could shim the bump steer out of the front at least.

Either way, I'll do a bump steer analysis of the front and rear so we can all see what we're working with. It'll make a good tech story for the mag.

Question for you all: are transmission problems common with the 8? During track testing I was having a hard time shifting quickly into 4th gear at first. Was getting a nasty grind, so I had to slow the shift down and apply very light pressure with the lever for it to slide in smoothly. By the end of the night I wasn't losing much time shifting this way, but I was kinda bummed out to find 4th gear being so uncooperative at first.

I also noticed some high-pitched whining, presumably from the gearbox, during the drive home. I'm going to put some high quality gear oil in the box to see if that cures it, but strangely the whine was quite noticeable in 4th and 6th gear but completely gone when cruising in 5th gear. Weird!

I'll also admit that I spent some time looking for the DSC kill switch only to eventually realize that my '05 Sport version doesn't seem to have DSC. LOL. She drifts quite nicely on the track -- definitely a more stable platform than a S2000, though I was surprised by how much body roll the 8 has compared to a S2k.

Question for you all: are transmission problems common with the 8? During track testing I was having a hard time shifting quickly into 4th gear at first. Was getting a nasty grind, so I had to slow the shift down and apply very light pressure with the lever for it to slide in smoothly. By the end of the night I wasn't losing much time shifting this way, but I was kinda bummed out to find 4th gear being so uncooperative at first.
.
The new oil may help . I tried Redline75w140ns (recommended by Teamrx8) and IIRC it did help with this .






I also noticed some high-pitched whining, presumably from the gearbox, during the drive home. I'm going to put some high quality gear oil in the box to see if that cures it, but strangely the whine was quite noticeable in 4th and 6th gear but completely gone when cruising in 5th gear. Weird!
.

Have always had that myself as well - I don't worry about it these days . It is just the way the shift lever transfers noise from the g/box . Some 8s do it most dont .
Try putting very slight pressure on the lever with your hand and notice how the noise dissappears .

Thanks Brettus, appreciate the feedback. I've had really good results using Redline MT-90 (1.5q) and a bit of Heavy Duty Shockproof (0.5q) in my Honda K20 transmissions on the race car, so I may try this recipe in the 8 too. I assume the 75w140 TeamRX8 recommends is the Light Duty Shockproof? Seems like my MT-90 + a bit of HD Shockproof is likely a similar overall blend to a full fill of LD Shockproof. Hrm. I guess I'll stick with what I know and try my MT-90 + HD and see how it works. I'll let you know how it goes!

What do you guys recommend for diff oil? Redline as well?

Speaking of diffs, has anyone here upgraded to a clutch-type LSD? Overkill given the low torque of the Renesis? Thoughts on me going with a OS Giken clutch-type an testing it against the OE helical-type? I saved 1-second a lap by going from the viscous LSD to a clutch-type LSD on my G35, so was hoping to find a similar savings with a diff upgrade on the 8.

EDIT: my car definitely has bad engine mounts, so it just occurred to me that this could have been contributing to the 4th gear shifting problem. I've also just read about a clutch pedal flex problem, so will look into that further too. Man, lots of little fixes to do to get my '05 in tip top shape!

Thanks Brettus, appreciate the feedback. I've had really good results using Redline MT-90 (1.5q) and a bit of Heavy Duty Shockproof (0.5q) in my Honda K20 transmissions on the race car, so I may try this recipe in the 8 too. I assume the 75w140 TeamRX8 recommends is the Light Duty Shockproof? Seems like my MT-90 + a bit of HD Shockproof is likely a similar overall blend to a full fill of LD Shockproof. Hrm. I guess I'll stick with what I know and try my MT-90 + HD and see how it works. I'll let you know how it goes!

!

It's just Redline 75w140ns (non slip) but yeah the MT90 is favoured around here as well and what I currently use .

Brettus, you also using MT90 in the diff?

Here's a few sexy-time pictures I shot last night in preparation for the RX-8 project car intro story...

http://i259.photobucket.com/albums/hh314/Modified_Dave/RX8wide1sm.jpg
http://i259.photobucket.com/albums/hh314/Modified_Dave/RX8wide3sm.jpg

Hi Dave,

Check out this thread on the Canada forum:

http://www.rx8club.com/showthread.php?t=195294

Jeff aka MazdaManiac is flying up to Toronto to do a tuning day with the COBB!

Thanks Alrib. Not sure if I'll have all the planned power adders installed by July 17, but once I figure that out I'll see about attending. Most likely I'll end up doing a custom tune with Sasha at SG-Motorsport or Dan from U2NDyno.com. These guys do the ECU tuning for many of the top race teams in the country including some rotary-powered cars.

Question for you all: are transmission problems common with the 8? During track testing I was having a hard time shifting quickly into 4th gear at first. Was getting a nasty grind, so I had to slow the shift down and apply very light pressure with the lever for it to slide in smoothly. By the end of the night I wasn't losing much time shifting this way, but I was kinda bummed out to find 4th gear being so uncooperative at first.

I think more transmissions have been killed by "slam-shifting" than by horsepower by a huge margin. I doubt you are slam-shifting, but it does sound like you may be rushing. I think it was John Muir (VW repairman) who said something like "all people and gears need is a little grease and a little space". I'd say it like "All transmissions need is a little grease, a little space, and a little time." You found like I did that give the synchros a little time to do their job and the gear engages easily. Eric Myer backs me up on this (http://www.rx8club.com/showthread.php?p=2787222#post2787222) (and recommends stock shifter and clutch). That thread is worth a read.

The RX-8 trans is good, but not all that strong. Somebody said (Eric, IIRC) they think it's because the PPF is on the wrong side, illustrating by saying the one Mazda transmission thought of as completely bulletproof is the one Miata transmission that has the PPF on the other side. (Can't find the thread.)

I had some trouble with the 3-4 shift when I got the car (15k miles on the clock), so after 5k miles put in Red Line MT-90. That smoothed things out nicely, but the 3-4 shift would still get stiff when running hot and hard on the track. So I just switched to SWEPCO 201 (http://www.swepcousa.com/lubesite/gear.htm) for this season. Now first is really stiff and cold the car tries to pull forward in neutral! But now the 3-4 shift is like butter on the track. That SWEPCO is some really weird sticky blue stuff. Here's the analysis results (http://www.rx8club.com/showthread.php?t=184241&page=11#post3577007) of the original fill at 20k miles and the Red Line MT-90 after 16k miles. I'll do the same for the SWEPCO after a similar number of miles. I'm still keeping my eyes open for an improved 2009-10 trans cheap. :)

I also noticed some high-pitched whining, presumably from the gearbox, during the drive home. I'm going to put some high quality gear oil in the box to see if that cures it, but strangely the whine was quite noticeable in 4th and 6th gear but completely gone when cruising in 5th gear. Weird!I think that's pretty common. I get the same thing, though I do have a short-shifter installed (not really that fond of the SS anyway).

I'll also admit that I spent some time looking for the DSC kill switch only to eventually realize that my '05 Sport version doesn't seem to have DSC. LOL. She drifts quite nicely on the track -- definitely a more stable platform than a S2000, though I was surprised by how much body roll the 8 has compared to a S2k.HA! :D: Be happy you don't have it! One less system to fail or hassle with. Eric had his ABS fail leading to an agricultural excursion, which tempts me to disable mine on the track so I don't rely on it and have it fail at a bad place. If yours is the "stripper" car like mine, you also don't have the silly HIDs and associated leveling system, fogs, leather seats, or Bose system. All that stuff just adds weight. My buddy who was the original owner of my car swears Mazda made these no-sunroof strippers just so the racers could have a lighter, low-option car to start with. Dealers didn't seem to stock many.

Interesting comments about S2K vs. RX-8. A friend of mine is big into the S2K world and has a very, very quick yellow one (#141). I'll have to let him drive my 8 and see what he thinks. After my latest spring and alignment job, I think my car is perfectly balanced. At the limit it is just unflappable, but I can still induce under- or over-steer with just the right input. I just can't get over how good the RX-8 is. Zoom-Zoom! :icon_tup:

Thanks wankelbolt, I appreciate the feedback. Once I got more patient and smooth with the 3-4 shift it did seem to go into gear quite happily. I had to use less forward pressure on the shift lever than I'm accustomed to, but only on the 3-4 shift. Anyway, seems like some driver tuning and some better trans fluid will take care of it. I'll definitely watch for your SWEPCO fluid analysis. Never heard of the stuff. I'm going to try some Redline in the meantime.

So here's a new riddle with my "box of chocolates" RX-8 (which is indeed the base GS model with cloth interior, no sunroof, no HIDs, no DSC/TCS or any of that weight adding garbaggio). Just did a couple quick pulls on the U2Ndyno.com Dynapack, which is quite pessimistic compared to any other dyno I've ever tried including the local Mustang dyno which is notoriously pessimistic. Knowing that the dyno is pessimistic, I wasn't too disappointed with a peak value of 162 hp and 119 tq, but I'm a bit concerned to see hp peak so early. From what I gather taking a quick look at the main dyno thread hp should peak around 8k rpm, not 7k like it does on mine. Any thoughts on why hp is peaking a little early? CAI effect? Bad coils? The engine does have fresh oil in it and fresh leading spark plugs (but I haven't installed the fresh trailing plugs yet), but I have not inspected the coils or wires yet. Anyway, any thoughts on this are appreciated!

http://i259.photobucket.com/albums/hh314/Modified_Dave/pratterx8.jpg

/\ classic case of stuffed coils

/\ classic case of stuffed coils

Really? Thanks Brettus, I'll order me some fresh coils tomorrow! I'll redyno as soon as I install the coils so we can confirm. Do you recommend changing the wires (about 40k miles on them, assuming they're original) while I'm at it?

absolutely yes .
Get some high quality leads with good connections - made a big diff for me . (autoexe)

OR get the BHR coils if you are allowed to use aftermarket coils .....

Thanks Brettus. You live in NZ? I spent a month there a few years ago and loved the country and was impressed by the car culture. Tons of nicely tuned Subarus and Nissans (plus some of those Aussie V8s), though I can't say I saw any RX-8s while I was there.

I know of a few who have had luck with stock coils but I know of no one who has had BAD luck with the BHR coils. I highly recommend them if the rules allow.

I highly recommend them if the rules allow.
Actually, aftermarket ignition systems are allowed in stock class. So yes, they're legal for STX.

Thanks Brettus. You live in NZ? I spent a month there a few years ago and loved the country and was impressed by the car culture. Tons of nicely tuned Subarus and Nissans (plus some of those Aussie V8s), though I can't say I saw any RX-8s while I was there.

8"s are becoming popular here as they get within reach of the boy racers . Almost all of them are imported from Japan . Very few people have any idea of the potential of the car as a track weapon though as it has never featured in any kind of racing here . There is no racing class that suits it.

Just a minor detail you may not have come across yet. The tach reads high (you may have noticed it goes to 9,500 before the power gets cut. Well that is really 9,000 rpm. I think my current car is 300 to 400 rpm high at 8,300. People including Eric Meyer say there is no reason to run up to redline - no power there and potential extra wear. I have set my personal redline at 8,500 indicated (where the tone goes off) so the engine lasts good and long.

What events do you plan on doing this year? Any National Tour's or Pro's before the Championships in September?

ganseg, thanks for that. We were wondering about the tach while dyno testing it, since we noticed it was reading a good 400 rpm higher than the dyno was indicating. Looking at dyno graphs for healthy STX 8's like GeorgeH's, assuming I can make mine similarly healthy, I will definitely shift at around 8 to 8.5k rpm since there doesn't appear to be any reason to rev it higher than that. Might stretch it to 9k when the course layout requires it.

TopGear8, I'll definitely be at the Seneca Lake, NY National Tour event in July (though the car won't be fully STX maxed out by then, I don't think). I'm putting together a little posse of fellow Canucks to come down with me. We'll bring maple syrup and back bacon to pay off the tech inspectors and highway patrol :p Other than that, I'll take it to a bunch of local autocrosses and time attack events to get the 8 dialled in to my liking (and to have some fun). Might take it to the NASA weekend at BeaveRun at the end of June since I love that little track and it's not too bad a drive from where I live (close to Niagara Falls).

I'm thinking of doing either the Finger lakes NT or the Peru NT. Haven't decided which one at this point. If I do attend FL, I'll be sure to say hi in grid.

Would be great to meet you, chiketkd. We can paddock together for the double gray RX-8 effect :)

Actually, I'll see if I can some 255/40-17 RE-11s in time for this event so I can test them against the 265/35-18s like we talked about earlier in this thread. I have a buddy with some 17x9 RPF1's, so should be g2g on the wheels. Just need Bridgestone to play ball, which I think they will.

Are you planning to test the car at any track days at Mosport (Kensai, 6th Gear, Apex, etc)?

Let us know what track days / Solo 1 events you will attend, a few folk from the Toronto area may come out to check out the car and your progress.

What kind of alignment settings are you planning?


Subscribed to the thread.

Hey Chris, I'm going to be at the SoloSprint events at Toronto Motorsports Park on June 19th and 20th competing in the RX-8 in GT3. Might be there on the 18th as well for some testing and tuning.

Dave, I'm the organizer for the Sunday SoloSprint event on behalf of TAC and HADA is the organizer for the Saturday SoloSprint event. Looking forward to seeing your 8!

Dave, I'm the organizer for the Sunday SoloSprint event on behalf of TAC and HADA is the organizer for the Saturday SoloSprint event. Looking forward to seeing your 8!

Thanks Alrib! What class are you running in?

GT3, since I'll be on used Grand Am Hoosier tires.

GT3, since I'll be on used Grand Am Hoosier tires.

Grand Am Hoosiers? Nice! We'll have quite an interesting comparo of street tires + coilovers vs r-comps + stock suspension. Should be fun! Guess I'll have to install some fresh ignition coils to make sure the old Renesis is in tip top shape for this epic battle at TMP :boxing_sm

I've also heard this Grand Am Hoosiers.. I think it will be a lot of fun!

Anything new on the suspension geometry relative to lowering? I went with only the 1" drop up front based on strong advice from here. But now I have a decision to make - my car is understeering and it seems to me lowering the front more would give me more grip. I hate raising the rear or increasing the rear sway bar, since it seems to me that is just lowering grip at the rear to make up for my problem.

I could go to zero toe in the rear, but that is hard having come from BMW which have enough give with stock busings to go to toe-out under compression. I don't want that much oversteer on a high speed track.

In my experience, your instincts are correct - drop the front a little and you should get more front grip. With the KWs, you can go more than a 1" drop without having bump-stop issues, and IMO the geometry can handle it as well. Just drop it one or two turns - you'd be surprised what that will get you.

And, I'd stay away from zero rear toe. You'll probably just end up with corner-exit oversteer.

[edit] I should add that my comments are relative to SOLO use. I've no experience setting up an RX-8 for high-speed track use. If that is your application, it is possible that going lower in the front will result in objectionable amounts of bump-steer.

Dave, I would suggest starting your pulls at as lower RPM (like 2,000 or so). That way, we can verify the SSV opening as well as the other valves. At 6,250 and 7,250 we can see the APV and whatever the HELL the other one is called (I can never remember, LOL) as that is where we see slight dips in torque during the transitions. I would also suggest using less smoothing on the printout so we can look at more detail. Even brand-new OEM coils will create a "picket-fence"above 7,000 RPMs, which the BHR Ignition System will cure.

Dave, I would suggest starting your pulls at as lower RPM (like 2,000 or so). That way, we can verify the SSV opening as well as the other valves. At 6,250 and 7,250 we can see the APV and whatever the HELL the other one is called (I can never remember, LOL) as that is where we see slight dips in torque during the transitions. I would also suggest using less smoothing on the printout so we can look at more detail. Even brand-new OEM coils will create a "picket-fence"above 7,000 RPMs, which the BHR Ignition System will cure.

Thanks Charles, will revise our dyno technique as suggested and looking forward to getting rid of that picket fence!

ganseg, I haven't done a bump steer or roll center analysis yet but will do so in the next few weeks. I just installed a set of BC coilovers last night and I'm doing a string box alignment right now, prepping it for the track tomorrow. I'll let you know how the car behaves at the track along with my ride height and alignment settings, as we dial both in during testing tomorrow. I have no idea what to expect from the BC dampers both in terms of overall performance and adjustability, but only one way to find out. Given how inexpensive these coilovers are, I'll have to keep my expectations realistic. They ain't going to outperform the Motons on my racecar, of that I'm fairly certain.

Bump-steer? Really?

Unless your RX-8 is drastically lowered (negative rate on the lower control arm), the RX-8 doesn't exhibit bump-steer.
The geometry of the front suspension is setup to negate any changes that happen in toe from compression.

Bump-steer? Really?

Unless your RX-8 is drastically lowered (negative rate on the lower control arm), the RX-8 doesn't exhibit bump-steer.
The geometry of the front suspension is setup to negate any changes that happen in toe from compression.

Good to know, thanks Jeff! My buddy has a bump steer rig, so we'll test it anyway, just so we've got some data to show off.

The general consensus among the RX8 Solo/Race guys here seems to be not to go lower than 13 1/2'' to 13 1/4'' ride height (strangely, the convention here seems to be to measure from the center of the wheel to the fender lip, though I prefer to measure from the ground to the chassis sill since those are easier to consistently measure from), but I may try running a little lower than that to see if the car exhibits any strange behaviour. Maybe the primary concern is running out of bump travel on the dampers, rather than bump steer or other geometry problems coming into play.

strangely, the convention here seems to be to measure from the center of the wheel to the fender lip, though I prefer to measure from the ground to the chassis sill since those are easier to consistently measure from


The problem with measuring to the ground is you are adding the tire to the equation. 2 PSI in the tire can change your measurement by 1/4"!
Center of hub to fender is a know quantity and doesn't change with temperature/wear/pressure/etc.

I hope this doesn't indicate a problem - my ride height changes by 1/2 inch between times I measure it. I would notice one side of the rear of the car was lower, next time it wouldn't be. I think the front does this too.

The problem with measuring to the ground is you are adding the tire to the equation. 2 PSI in the tire can change your measurement by 1/4"!
Center of hub to fender is a know quantity and doesn't change with temperature/wear/pressure/etc.

That's a good point, Jeff. I always make sure my tire pressures are the same when measuring ride height, but tread wear could certainly contribute to changes if I was monitoring ride height regularly (which I don't tend to). I just find it hard to accurately and repeatably find the center of the hub, whereas I can always find the ground :) Plus I'm not sure the fender is really always in the same place. My fenders are already kinda beat up.

Anyway, I'm just using ride height to establish a reasonable starting point from which to corner balance the car (after which the ride height will be a little different at each corner, obviously).

Dave, I'm the organizer for the Sunday SoloSprint event on behalf of TAC and HADA is the organizer for the Saturday SoloSprint event. Looking forward to seeing your 8!

Alrid, sorry I wasn't able to make it out this weekend. My pregnant wife was sick and I had to stay home to take care of her. I should be at event 5 at Mosport in a few weeks.

Which issue is likely to have the first article? I'll be picking it up!

ganseg, first story is in the September issue and then there will be regular (more or less monthly) stories from that point on. Was planning on going to the Finger Lakes National Solo Tour event this weekend and doing an upcoming story on it, but my wife is still in rough shape so I'll be at home taking care of her. I did sneak away last Saturday for a local SoloSprint (Time Attack) event, where I was able to get some good testing in with the BC coilovers. For an inexpensive street coilover kit they stood up to track abuse pretty well but for track days stiffer springs would definitely help (I was getting onto the bump stops a fair bit). I haven't looked at the official results yet but I think I finished 2nd in class behind a well-driven and prepped S2000.

ganseg, to go back to your comment about your ride height changing, that sounds to me like maybe you're taking measurements on uneven ground, though your springs will settle a bit after being installed and over time will sag a bit. I've found that if I take ride height measurements in different spots on my smooth and level concrete garage floor the numbers will still vary, so I've put down tape so that I'm taking my measurements in the same place every time. Helps a bit with consistency.

Here are a few pics from the SoloSprint event (including one of a nicely prepped Pettit supercharged 8...not sure if the owner is a member here or not):
http://i259.photobucket.com/albums/hh314/Modified_Dave/Red8.jpg
http://i259.photobucket.com/albums/hh314/Modified_Dave/RX8DDT2sm.jpg
http://i259.photobucket.com/albums/hh314/Modified_Dave/RX8DDT3sm.jpg
http://i259.photobucket.com/albums/hh314/Modified_Dave/RX8DDT4sm.jpg
http://i259.photobucket.com/albums/hh314/Modified_Dave/RX8DDT6sm.jpg
http://i259.photobucket.com/albums/hh314/Modified_Dave/RX8sunset2sm.jpg

Very cool - thanks for the pics!

That red car sits higher than mine. He must come from the only drop the front 1".

I measure my car in the same spot in my garage. It only has a little slant to help water drain. There is another guy with KW3s that noticed the same issue.

On the ride height measurements, have you tried bouncing each corner of the suspension before taking the measurements, to encourage the suspension to fully settle? I find if I have the e-brake on and I don't give the car a bit of a bounce on each corner, the ride heights can be a little less consistent. If you have any binding of suspension bushings or swaybar endlinks, this could also contribute to changing ride height readings.

I think the red RX-8 is running 17'' wheels and tires, so that may be tricking the eye a bit in terms of ride height/fender gap. He definitely hasn't lowered it too aggressively though, which I'm sure is a good thing given how the front double wishbone gains camber actively during roll anyway. Definitely no point in going too low with these cars. My ride height is now at 13.5 all around and I may go up a 1/4'' to see how that affects handling. But first I'm going to try stiffer springs at this ride height.

Read the tire article in Modified and 4 seconds is very impressive, It's nice to see the RX-8 finally getting some proper coverage and being modified in the proper way. Can't wait to follow the build!

Good write-up so far

I have bounced it, and I don't use the parking brake in my garage. I am going to let it go. i am now about 13.5 all around. The handling feels good so i think i will leave it here until i get a chance to go to the track - I can change heights on the fly there as well as dampening. Thanks for all you are doing with the car, posting here and the articles!

Actually, aftermarket ignition systems are allowed in stock class. So yes, they're legal for STX.

It's permitted to change ignition coils, ignition wires, and sparkplugs.

Nothing says that you're allowed to remove or replace the OE coil mounting bracket ....


.

caught the write up on tires in the latest modified mag, car is looking really nice

Nothing says that you're allowed to remove or replace the OE coil mounting bracket ....
True - but the mounting bracket could be seen as being part of the ignition coils. It serves no other function than keeping the coils secured.

True - but the mounting bracket could be seen as being part of the ignition coils. It serves no other function than keeping the coils secured.
What comes in the box when you buy a coil?

What comes in the box when you buy a coil?
A coil.

I just don't see an alternate means of securing an ignition coil system in the stock location as being illegal.

I have no interest in arguing this point further. Maybe I'll send an e-mail to Doug Gill and/or submit a letter to the SAC for clarification.

Internet banter gets us nowhere.

That's what was said about the front intake shroud ....

Nothing says that you're allowed to remove or replace the OE coil mounting bracket ....


.


Since when do you remove or replace the OEM coil mount when putting in BHR coils? :dunno:

I left mine in the stock location, and put the BHR coils right on top of it...

Since when do you remove or replace the OEM coil mount when putting in BHR coils? :dunno:

I left mine in the stock location, and put the BHR coils right on top of it...
That's a good point. Stock mount is still in it's place - the BHR coils just come attached to a mount. if you order a BHR ignition coil system, they come bolted to the BHR mount as one piece. The whole contraption slides down on top of the stock mount/mounting location and nothing is modified and completely reversible.

When I get the time I'll formulate a letter and send it to Doug Gill first. If he feels it needs clarification from the SAC then I'll send it on to them. Work is just busy right now and I've decided to go back to school starting next month to get a 2nd degree. My mind is on Polynomial equations and Group Theory right now and not autocross...

Btw, for those not familiar with the BHR ignition system - this is what it looks like when you get it in the mail:

http://i32.photobucket.com/albums/d14/Chiketkd/Mazda%20RX-8/STX%20Build/BHRIgnitionkit_1.jpg

And here's a pic I snapped after installing it in my STX car (never had it when I was in Stock class):

http://i32.photobucket.com/albums/d14/Chiketkd/Mazda%20RX-8/STX%20Build/BHRIgnitionSystem.jpg

well my bad then, I thought the OE bracket was replaced :dunno: in that case never mind and don't bother writing a letter, totally my bad. I never had a BHR bracket, made my own instead when I ran those coils for a while.

FWIW I put the OE coils back on ....



.

FWIW I put the OE coils back on ....

.

dare i ask ....



why ?

well my bad then, I thought the OE bracket was replaced :dunno: in that case never mind and don't bother writing a letter, totally my bad. I never had a BHR bracket, made my own instead when I ran those coils for a while.
That's good to hear.

Thanks to tiresmoker for his input - it's been several months since I installed mine that I forgot the stock mount wasn't removed myself. I just need sleep...

Just read the Sept article in Modified. Sure is great to see our cars written up. I am looking forward to more of that detailed analysis and articles to keep in my collection of favorites like the articles on the '86 MR2 I had 20 some years ago. :)

Hey Dave,
Great thread. Stumbled upon it and didn't even realize you were running an 8 now.

Are you running the Solosprint event at Mosport in a few weeks? I'll be back in action after quite a few years away, will be good to catch up. Probably same class also, in GT3.

I'll have to pick up the magazine and give it a good read.


Cheers,

Hey Dave,
Great thread. Stumbled upon it and didn't even realize you were running an 8 now.

Are you running the Solosprint event at Mosport in a few weeks? I'll be back in action after quite a few years away, will be good to catch up. Probably same class also, in GT3.

I'll have to pick up the magazine and give it a good read.


Cheers,

Hey Andre. Great to see you on this forum. Didn't know you're into RX-8s. You sell that turbo Miata of yours? EDIT: Duh. Just spotted your sig. Welcome to the world or rotaries :)

Wish I could make the Mosport weekend, but I'm away on business on those dates. What are you going to be driving at Mosport? Your RX-8, I assume?Hopefully I'll be at the Shannonville season ending weekend, so maybe I'll see you there?

ganseg, I don't think I've even seen the Sept issue yet. LOL. I always get them late up here in Canada. Was that the BC coilover story? Unfortunately I had a bit of a problem with my driftbox finding satellites that day so didn't get much usable data, but I'm going to retest again with some different swaybars at which point I'll introduce a bunch of interesting in-car data.

Hey Andre. Great to see you on this forum. Didn't know you're into RX-8s. You sell that turbo Miata of yours? EDIT: Duh. Just spotted your sig. Welcome to the world or rotaries :)

Wish I could make the Mosport weekend, but I'm away on business on those dates. What are you going to be driving at Mosport? Your RX-8, I assume?Hopefully I'll be at the Shannonville season ending weekend, so maybe I'll see you there?


Not sure about Shannonville. Been pretty busy at work so I picked a weekend to get back in it, and the Mosport event fit in well with my holidays. I can hopefully put on a good showing, got a new NT-01/RPF1 combo to try out. Too bad, saw your name from previous event results and wanted to go up against you. Maybe at SMP...

This thread is tits. Whats next for the 8??

This thread is tits. Whats next for the 8??

Just did a ARK Design MFD (multi-function display) yesterday with oil temp, oil pressure and water temp sending units and Racing Beat water temp adapter and oil adapter. Also working on a trunk mounted Odyssey PC680 battery with a West Coast Batteries bracket. These will be in the Nov issue I think. Lots of other cool stuff coming from BHR, Racing Beat, Cobb, Mazdaspeed and others.

I absolutely love driving this car at the race track. It's wonderfully balanced and rewarding to drive on the limit. It just needs an extra 100-hp or so :) I think we'll get maybe half way there with all the mods planned, but that next 50+ hp may require something a little more extreme. Anyway, that's long-term since the main thing right now is to get the car prepped to the full extent of the STX rules so I can take a reasonably competitive package to the Solo Nats next month. After that I think I'll prep it for Time Attack and see about that big horsepower upgrade.

Nice to see an 8 being built right.

Nice to see an 8 being built right.

not only that but that it still has the rx8 engine and not a swap in it

not only that but that it still has the rx8 engine and not a swap in it

Hell yeah. I love a good swap but I was really sad when I bought this car and found that 400 hp was rare and unstable for the renesis. I always read about FD's making 850 hp.... I know our 8 is not a corvette but damn. I saw the Emersil turbo that someone got 500 with... But seriously, we need to make the Renesis a real competitor or keep waiting for the 16x :(

Hell yeah. I love a good swap but I was really sad when I bought this car and found that 400 hp was rare and unstable for the renesis. I always read about FD's making 850 hp.... IYou may make that much power for a couple of dyno runs, but that would also be rare and unstable for an FD. A streetable FD will come in around 450 to 500 hp tops.

Gotta at least appreciate n00bs for teh enthusiasm ....

Gotta at least appreciate n00bs for teh enthusiasm ....

He has no idea how lucky he is right now. :lol2:

You may make that much power for a couple of dyno runs, but that would also be rare and unstable for an FD. A streetable FD will come in around 450 to 500 hp tops.
Interesting. That gives me a little more hope for our motors.

for most applications, anything over 600 hp in unusable, FOR THE MOST PART. that much hp can obviously be utilized but it takes lots of time, work, and money.

Hell yeah. I love a good swap but I was really sad when I bought this car and found that 400 hp was rare and unstable for the renesis. I always read about FD's making 850 hp.... I know our 8 is not a corvette but damn. I saw the Emersil turbo that someone got 500 with... But seriously, we need to make the Renesis a real competitor or keep waiting for the 16x :(
hell yea... i waiting to buy it when i get back from overseas..... just had my tranmission redone, new clutch and gaskets bearing and syncros all done by 30,000 miles

for most applications, anything over 600 hp in unusable, FOR THE MOST PART. that much hp can obviously be utilized but it takes lots of time, work, and money.

New tranny.
New driveshaft.
New PPF.
New rear suspension links.
New rear axles.
New differential.

And that is just the driveline/suspension............

New tranny.
New driveshaft.
New PPF.
New rear suspension links.
New rear axles.
New differential.

And that is just the driveline/suspension............

Charles, what do you consider the safe power limit of the Renesis with forced induction (I'm thinking about a custom Rotrex supercharger install) if you want to run pump gas and maintain good daily drivability/reliability but also lay a beating on it at the track from time to time?

Charles, what do you consider the safe power limit of the Renesis with forced induction (I'm thinking about a custom Rotrex supercharger install) if you want to run pump gas and maintain good daily drivability/reliability but also lay a beating on it at the track from time to time?


I'm gonna throw a 300-400 whp out there... 400 being on the high end as it is not common at all to see and I personally haven't seen a S/C do that yet... I'd say 310 - 330 at the wheels is where you see many people able to sit comfortably.

Charles, what do you consider the safe power limit of the Renesis with forced induction (I'm thinking about a custom Rotrex supercharger install) if you want to run pump gas and maintain good daily drivability/reliability but also lay a beating on it at the track from time to time?

Do you still have my cell number? ;)

I'm gonna throw a 300-400 whp out there... 400 being on the high end as it is not common at all to see and I personally haven't seen a S/C do that yet... I'd say 310 - 330 at the wheels is where you see many people able to sit comfortably.

Based on mere statistics? There are SO many variables involved and so few F/I'd Renesis engines, relatively speaking, that mere statistics will not suffice. Not IMO, anyway.

Do you still have my cell number? ;)

Yes.


:dunno:

n00bs will be n00bs .....

n00bs will be n00bs .....


Everybody is a noob.

Yes.


:dunno:

"The world does not start and stop at your convenience, you miserable piece of......"

Walter from The Big Lebowski

Everybody is a noob.

Everybody will be everybody ... Except in the case of a n00bette such as yourself :stickpoke

Based on mere statistics? There are SO many variables involved and so few F/I'd Renesis engines, relatively speaking, that mere statistics will not suffice. Not IMO, anyway.


haha based off mere statistics is exactly where that is from...That's all I have to go off up here haha.... but one day when budgeting is of less concern and I am more knowledgeable in the world of FI I mean to test this engine so I can give an answer from first hand experience. Not to mention FI'd Renny's should slowly become more affordable :D:

Just did a ARK Design MFD (multi-function display) yesterday with oil temp, oil pressure and water temp sending units and Racing Beat water temp adapter and oil adapter. Also working on a trunk mounted Odyssey PC680 battery with a West Coast Batteries bracket. These will be in the Nov issue I think. Lots of other cool stuff coming from BHR, Racing Beat, Cobb, Mazdaspeed and others.

I absolutely love driving this car at the race track. It's wonderfully balanced and rewarding to drive on the limit. It just needs an extra 100-hp or so :) I think we'll get maybe half way there with all the mods planned, but that next 50+ hp may require something a little more extreme. Anyway, that's long-term since the main thing right now is to get the car prepped to the full extent of the STX rules so I can take a reasonably competitive package to the Solo Nats next month. After that I think I'll prep it for Time Attack and see about that big horsepower upgrade.


I hope this thread can get back on track with you. It is a lot of fun seeing this written up.

1).... but one day when budgeting is of less concern and I am more knowledgeable in the world of FI I mean to test this engine so I can give an answer from first hand experience. 2) Not to mention FI'd Renny's should slowly become more affordable :D:

1) By then, BHR will have published everything anyone will want to know.

2) How so?

2) How so?


Cheaper to purchase an Rx8 therefore more people will take it FI.

Cheaper to purchase an Rx8 therefore more people will take it FI.

How much cheaper does it need to get before people are willing to risk their Renesis engines because their buddy, who tunes Hondas all day long, decides that Renesis engines are no different than piston engines? We are on our 4th and 5th generation owners these days, RX-8s can be had for less than $10K, and I am not yet seeing this trend you are hoping for. There are many people inquiring about going F/I but they cannot afford to lose their engines MORESO than those of us who got our cars when they first came out.

Think of it this way; rebuilding Renesis engines will not get cheaper. Therefore engine replacement cost is becoming a greater percentage of the purchase price of the car, itself.

That is just my theory, though.

This is all just sidebar conversation until Dave resumes posting about his mods, anyway. Classroom murmur, if you will........ :lol:

My 8 only cost me $11k, which I think is a heck of a deal for a low mileage sports car that's this much fun to drive. With 300whp, it'd be plenty fast given that it's a relatively lightweight chassis. I'm tempted to do something silly like a V8 swap, but before I go anywhere near that I'm going to port the Renesis and see what kind of naturally aspirated power I can get out of it and then I'm going to look at a low boost supercharger setup. No point in doing a complex and expensive V8 swap if I can get the Renesis to a power level I'm happy with and is reliable.

Speaking of reliability, here's a couple pics of that ARK Design MFD gauge unit I recently installed. It's a pretty cool little device and doesn't clutter up the interior at all. I like the fact that it stores peak temp and pressure values so that I can review them after a track session where both water and oil temp are critical to keep an eye on with these engines. I'm curious to see if I get a water temp drop on track once I relocate the battery to the trunk. Will report back on that one once the battery relocation is done and I've been out to the track again for testing.

http://i259.photobucket.com/albums/hh314/Modified_Dave/ARKMFD1.jpg
http://i259.photobucket.com/albums/hh314/Modified_Dave/ARKMFD2.jpg

Took a couple glam shots recently for an upcoming story that I thought I'd share too while I'm at it.

http://i259.photobucket.com/albums/hh314/Modified_Dave/rx8rig1sm.jpg
http://i259.photobucket.com/albums/hh314/Modified_Dave/RX8graffiti1sm.jpg

Gotta get some MS sideskirts to go with the front bumper, plus I've got a really nice custom wing from DJ Racecars in the UK that we'll be making some nice mounts for so it can call the 8's trunk home. Going to build a custom removable front splitter too for Time Attack use, kind of like the one I built for my racecar:

http://i259.photobucket.com/albums/hh314/Modified_Dave/SplitterMount_Colored.jpg
http://i259.photobucket.com/albums/hh314/Modified_Dave/SplitterMount_Colored2.jpg
http://i259.photobucket.com/albums/hh314/Modified_Dave/SplitterMount_Colored3.jpg
http://i259.photobucket.com/albums/hh314/Modified_Dave/SplitterMounts4.jpg

Gotta thank the noob-lovin' TeamRX8 for his post about HJS Motorsports, since I got my hands on one of their WRC catalytic converters and will build that into the Racing Beat midpipe I have on the way. I'm excited to see how this cat works out, since I've only ever tried consumer-grade high-flow cats before. This thing is a true hardcore motorsports cat so it'll be interesting to see how durable it is and what kind of power it frees up.

Thats a clean civic, very nice

Dave does the ARK operate via OBD II or is it a direct plugin? I've been looking for a replacement for the MSD DashHawk for a while now but haven't found anything that I liked.

Everybody will be everybody ... Except in the case of a n00bette such as yourself :stickpoke

I need me some fried chicken. Finger lickin' good!

http://i642.photobucket.com/albums/uu150/edenthegoddess/fried_chicken.jpg

By the way, the car is looking good Dave!

I need me some kara-age. Finger lickin' good!




Fixed, eat mo' washoku .....

Fixed, eat mo' washoku .....

OK :yumyum:

http://2.bp.blogspot.com/_AdeUgwXpSAM/SKenYwQhUaI/AAAAAAAAJss/v2dfB6Qgy5U/s400/kaisekifood.jpg

Dave the car is looking sexy... I've been in love with those wheels since I ever first saw them; I think they'd look good on my LY!

Classroom murmur, if you will........ :lol:

You raise a valid point though, unordinary car... unordinary trends.

Oh well, the less FI 8's I see around here the more prestigeous I get to feel :D:

You raise a valid point though, unordinary car... unordinary trends.

Oh well, the less FI 8's I see around here the more prestigeous I get to feel :D:

Based on professional experience.

The most prestige one can feel while owning an F/I Renesis is by having it run strong and not be a PITA on the maintenence, which is completely possible.

Dave does the ARK operate via OBD II or is it a direct plugin? I've been looking for a replacement for the MSD DashHawk for a while now but haven't found anything that I liked.

It's a direct wire-in, so a bit of a PITA compared to a OBD-II device but still very easy to do since the ARK wiring harness has nice little plugs built in to connect to their optional temp and pressure sending units. It also has a line built-in for vacuum. I'll post some more detailed pics when I get a chance.

Thats a clean civic, very nice

Thanks! I've had it since '99 and have slowly built it into a full racecar (ran it for a few seasons in the Canadian Touring Car Championship). I'm actually thinking about selling it since the 8 is probably going to evolve into a racecar eventually (or at least a dedicated track car). If you know anyone looking to buy a supercharged K24-powered Civic making 412whp, lemme know :)

Dave, I am interested in your comparison of the RX-8 to other cars you can buy for under $15k and take to the track. For me it has to be a daily driver, so I am not asking about a car to make a dedicated track car.

This is the best handling car I have ever owned. When mine was stock, it was very neutral but the springs were too soft for the track. I have added KW3s and have R comps and track pads for track days. I would love to add power, but that is unlikley. I cut 3 seconds off my lap time the first day out compared to my E36 M3 (also lightly modified) on Brainerd's long course.

sub

Dave, I am interested in your comparison of the RX-8 to other cars you can buy for under $15k and take to the track. For me it has to be a daily driver, so I am not asking about a car to make a dedicated track car.

This is the best handling car I have ever owned. When mine was stock, it was very neutral but the springs were too soft for the track. I have added KW3s and have R comps and track pads for track days. I would love to add power, but that is unlikley. I cut 3 seconds off my lap time the first day out compared to my E36 M3 (also lightly modified) on Brainerd's long course.

At a recent local Time Attack event I ran against a similarly prepped S2000 on street tires with a top quality driver and I ended up being about 1-second off his best lap time. The S2000 driver, Jonathan Weir from Honda Canada and Enmo Racing, took my RX-8 for a ride at the end of the day during open lapping and he was surprised how long the gearing is and how down on power the 8 is compared to his S2K (he came within about 6/10ths of my best lap time in the 8, which was impressive since he only did 6-7 laps). There was also a fast 350Z in our class that posted some very good lap times, and both the S2K and the 350Z can be had in or around your price range. But they're both 2-seaters so not as practical as the 8 for daily driving. Both have distinctly different characters to the 8 as well.

The S2000 feeling harder edged and twitchier at the limit but once you get a handle on it you really feel the chassis communicating to you. It also has a wonderful engine (makes about 200-205whp stock but has lots of tuning potential in both NA and FI forms) and excellent build quality, LEV status, and surprisingly good fuel economy.

The 350Z feels like a bigger heavier car but is still very responsive also has a nice V6 that produces good torque, something the 8 is seriously lacking. The Z also gets better fuel economy than the 8 (my G35 coupe averaged 24mpg city/highway combined). The V6 isn't all that receptive to NA tuning, though more so than the Renesis.

Another interesting option might be a E46 M3. These are really coming down in price and they're a heck of a lot of car for the money. You'd have to go for an early one to get down into the $15k range, but these cars are really fun to drive, have a great high revving engine, are very nicely put together overall, and have tons of aftermarket support but are a bit pricier in terms of modifying them.

Man, I could play this game all day :)

The S2000 is always high on my list. Is the oversteer issue on the early ones a problem or is it a good thing for someone that knows how to use it? (I don't know how to use it yet, but that's why I moved to the RX8 from the M3 is to learn skills in a more neutral car.) Two of the tracks I go to have high speed corners (Brainerd turn 2 at 115 and Road America), so I don't want it to oversteer insanely.

Man, I could play this game all day :)

So could a lot of us :). I had a 350z for about 4 months. Sadly the dealer could not get the paperwork together (stolen?), but they made the mistake of letting me take it home so I never paid for anything but insurance :D Honestly, it was more like a Japanese version of my classic mustang than the 8. It was great at drifting, straights, hairpins, you name it. I even go to take it to Asheville where my parents live and rip through a few mountain roads I know like the back of my hand. I had zero complaints. Sure there was some stock issues like the rear hatch not working and all that but I'm a mechanic. I don't care about all that little stuff. I'd just assume gut it and drive a frame around. I was actually looking for a 35o when I found my 8 :D
Another car I know very well is the MR2 spyder. Talk about a fun car. The layout was so good and light that you could have fun going 5 mph looking for a parking spot in a buisy parking lot or during spirited mountain driving. The engine lays down a whole 95 rwhp! but the 2100 lbs. makes it all ok (unless you like straigt line speed). I would say it turns as good or better than the 8. The difference is that unless you have a few grand in suspension upgrades you will go flying off the road at the higher limits. I lost both my cars because once I lost control there was NO getting it back. The mid engine is great for cheap exotic-like performance. Stick a 2zz (celica gts motor) with a turbo and a new suspension and you'll be golden.

The S2000 is always high on my list. Is the oversteer issue on the early ones a problem or is it a good thing for someone that knows how to use it? (I don't know how to use it yet, but that's why I moved to the RX8 from the M3 is to learn skills in a more neutral car.) Two of the tracks I go to have high speed corners (Brainerd turn 2 at 115 and Road America), so I don't want it to oversteer insanely.

I think the AP1's oversteer is actually a really good thing for autox but can be pretty sketchy in high speed corners. But with a big front swaybar you can neutralize the AP1's tail happiness quite well and a rear wing will work wonders in those high speed corners. We put a APR splitter (mostly cosmetic, I think) and GTC-300 wing on our S2K project car a few years ago and it completely transformed the car on the race track. Went from really twitchy and loose to super stable with a touch of understeer in higher speed turns. FYI we were also running a OE hardtop on our S2K and perhaps that helped the wing work better than it might with the ragtop down.

Dave, are you going to be at Nationals next week? I have not seen you on the list yet..

Dave, are you going to be at Nationals next week? I have not seen you on the list yet..

Unfortunately I've had to put off the Nationals until next year. Progress on the car has been slower than expected and it's nowhere near STX prepped yet. Having just moved and with a pregnant wife, I haven't had enough time to build the 8 for the Nats. But on the upside this will give me plenty of time to get the car fully sorted for next year.

Just picked up the October issue - good article! The pics are great!

How'd you get -2.75 degrees of camber up front? I got -2 (I have dropped the front a little bit since I had the alignment, but not enough to get another -.75). If your tail happiness isn't cured, can you get some more negative camber in back?

How do you think the dampers work? That was a good price! I bought used KW3s for $450 and have been happy, but finding used is hard and risky.

Do you think the 8 will ever move up to a more prominent article? C&D just called an R3 the 3rd best handling car under $100k. That is impressive! Thanks for your good work!

Just picked up the October issue - good article! The pics are great!

How'd you get -2.75 degrees of camber up front? I got -2 (I have dropped the front a little bit since I had the alignment, but not enough to get another -.75). If your tail happiness isn't cured, can you get some more negative camber in back?

How do you think the dampers work? That was a good price! I bought used KW3s for $450 and have been happy, but finding used is hard and risky.

Do you think the 8 will ever move up to a more prominent article? C&D just called an R3 the 3rd best handling car under $100k. That is impressive! Thanks for your good work!

Glad you liked the story and pics. I didn't do anything special to get -2.75 degrees of camber. I just maxed out the adjusters and that's what I ended up with. Actually, I think I had as much as -3 on the passenger side by dialled it back a bit. Is that more than these cars can normally get with the stock arms and adjusters?

The tail happiness continues to be a problem, but I've got a big front sway bar on the way so hopefully that'll help, but I'm also going to try some more rear toe-in and perhaps some more rear camber as well. Definitely worth experimenting with alignment settings as a way of taming the rear a bit more.

$450 for a set of used KW's is a smokin' deal. Having run Variant 3's on my previous project car, I am a big fan of these dampers. The BC coilovers are more street oriented in their design, especially the rears which don't have quite enough travel for the track (I'm still getting on the bump stops pretty badly despite having raised the spring rates and rear preload quite a lot). Ultimately I may have to go to different dampers to get the car handling the way I want at the race track.

In terms of the 8 being moved up to a more prominent article, the next issue is dedicated to nothing but our project cars, so there's a 5 page story on the 8 including two large double-page spread photos, so I guess you could call that more prominent. And as the project evolves there will no doubt be issues where its story features more prominently than others. For example, when I go to the Nationals next year and win a trophy (LOL), I'm sure the car will be on the cover :wink2:

Yo Dave,

This is an awesome build, im happy to see the RX-8 getting some attention from Modified as a project car (Actually I think you guys have always been good about featuring rotaries pretty regularly). The articles are great and I'm loving following the build. I thought you might want to know though that for what it's worth (and for the sake of authenticity I guess) that the front strut tower bar is actually just the stock bar with a mazdapeed sticker on it, the mazdaspeed bar is carbon fiber. Anyway, keep up the good work, I can't wait to see the car in the next few issues!

I think the MAZDASPEED bar is an aluminum bar with a carbon fiber sticker over it for bling. An actual, structural, carbon fiber bar would cost way more than $250. :D:

Well, it says Mazdaspeed on it, therefore it must be a Mazdaspeed strut tower bar! Kinda like my tattoo that says "world's biggest stud" :p:

On the upside, I do have some legit MS parts coming soon, so that'll help the strut bar blend in.

Check out corksports upper strut bar its the best imho cuz it connects to the firewall

Check out corksports upper strut bar its the best imho cuz it connects to the "wafer thin" firewall

:lol2:

Not to mention that it would be illegal to run it in STX...

Great Advice!

Not to mention that it would be illegal to run it in STX...

Great Advice!
And unnecessary. No bar here.

all true, and yea its definitely aluminum covered in a carbon wrap (to amplify rigidity and strength of course!)

Great thread, having just picked up an 09 R3 that I plan on using to go cone killing, looking forward to the continuing story.

IMHO = in my humble opinion

I don't know stx rules...link?

IMHO = in my humble opinion

Or, "in my honest opinion" :wiggle:

"in my hokey opinion" is typically more accurate :p:

"IMHO" Idiot must have opinion.


Not aimed at anyone in particular.




Unless the shoe fits.

Hey Dave, whats next on the list?

Just picked up the Nov issue (must have come in yesterday). I can't diagnose it, but the dyno indicates a problem. Your hp should peak around 8200 and it is peaking at 7200. There are various valves that are supposed to open ip and maybe the last one isn't opening. (the dip in the 6000 rpm range is related to extra intake ports opening - causes a dip first but then lets it breathe more.

Just picked up the Nov issue (must have come in yesterday). I can't diagnose it, but the dyno indicates a problem. Your hp should peak around 8200 and it is peaking at 7200. There are various valves that are supposed to open ip and maybe the last one isn't opening. (the dip in the 6000 rpm range is related to extra intake ports opening - causes a dip first but then lets it breathe more.

Yup, there's definitely a problem. I thought it was tired old ignition coils, spark plugs and wires, but as you'll see in the next issue we've addressed that with some BHR products and although we do gain some peak hp and tq the early drop off in power is still there. So now I'm on to testing the three stage intake and checking for vacuum leaks. I'm also going to swap in a motorsports catalytic converter next week so perhaps that'll do the trick. Normally with a plugged cat I'd expect to see power loss across the board, which doesn't seem to be the case here, but it's worth a shot. Also have a Cobb AP that I'm going to plug in to see if we can see a lean condition or anything else unusual happening above 7k rpm. Perhaps an injector is misfiring or the knock sensor is pulling timing. It's still a mystery at this point, but we'll figure it out soon (I hope).

Sandman, in the Dec issue we upgrade the fuel pump, clutch pedal and ignition system courtesy of BHR, and then in the Jan issue we upgrade to a RB header, resonated midpipe with HJS cat. After that we'll tune the ECU with the Cobb AP, hopefully with Jeff from MM working his magic remotely. Then comes some racing buckets and a roll bar along with some swaybar testing and tuning. I also plan to do a wheel size test in the spring, using 17x10'' Enkei RPF1's with 255 RE-11s vs my current 18x10 Volks with 265 RE-11s. I may also upgrade to Moton Clubsports, since I'm having a tough time working around the limited rear shock travel with the BC coilovers. I also need to address the 4th gear engagement problem at high rpm (not a problem for Solo 2, but a big issue at the race track), so you'll likely see a story on refreshing the trans. Oh, and I've got some pretty trick aero stuff in the works too, though it remains to be seen if the rear wing will be STX legal next year (apparently there's discussion of making rear wings illegal for ST classes, but I haven't followed this too closely so I'm not too sure what the current status is on this). If not, I'll just run the aero bits on the car for Time Attack events. So far I've used the car more for Time Attack than Solo 2, so who knows, maybe we'll take the build in a new direction. Time will tell. I smell a supercharger in this car's future, but probably not until after the Solo Nats next year.

Cool, Modified mag needs to do an rx-8 edition release, with all rx-8 tech, and rx-8 showcases

Cool, Modified mag needs to do an rx-8 edition release, with all rx-8 tech, and rx-8 showcases

Yeah, we gotta do something to pump up the attention on the RX-8. I want Mazda to keep on building them and the aftermarket/used part market to keep rolling. it is sad AccessPort dropped us. At least Mazda is supporting racing.

FWIW on track days I am going catless and then putting my cat back in for street. I don't the cat holding all that heat under my car at the track. I you are running on the stock tune, I doubt you are lean. The ap can read the stock wideband sensor, so you can check your AFR. Stock is about 11 to 1 at WOT. If I had a turbo, that'd be nice!

Yup, there's definitely a problem. I thought it was tired old ignition coils, spark plugs and wires, but as you'll see in the next issue we've addressed that with some BHR products and although we do gain some peak hp and tq the early drop off in power is still there.
.

Can you post the dyno for after you changed the coils please - might help with diagnoses ....

Dave,

So now that you've had a good amount of time with the BC Racing coilovers. How do you personally like them overall?

I'm in the market for Coilovers, and I'm considering these. But if you had a chance to change to a different coilover setup, which would you choose and why?

in the Dec issue we upgrade the fuel pump, clutch pedal

might want to double check the STX rules.

since this is a "used" car buy, power may be down for a variety of reasons due to the previous owners lack of maintenance/ or abuse?
Compression/vac readings for example--i am sure yall know how to check out the rx8 engine lol.
One thing I found on mine was the fuel injectors were out of balance---to the point that one was actually leaking/dripping. You may want to check you injectors?
High rpm power lost is mostly due to as you have suspected--ignition based
changing the coils and plugs can sometimes give a car a 15 hp bump on the top end.
running premix at 1.5oz per gallon can also give you a slight bump up.

I dont know STX rules, but as far as transmissions --the 09 and later models have a much better box.
OD

You mean 1.5 ounces per gallon under special circumstances, like a track day? I run .5 per gallon on a regular basis and increase for track days. Dave, please note that when you go to the MM tune, that increases the amount of oil injected. That might mean you want to be more careful about how much premix to add to the tune.

A failing cat starts with power loss at high RPMs, which gradually evidences itself at lower and lower RPMs as time goes by.
As for fuel injectors benefitting from flow-balancing, I presented that data when I rebuilt my own engine and the OEM injectors can have flow variances as much as 10-15%.

Thanks for all the feedback, guys. I appreciate it.

Today I swapped on a RB header and resonated midpipe along with a HJS Motorsports cat (replacing the forward most resonator) and as you can see the top end is much improved but still flatter than it should be. Keep in mind when looking at this graph that the dyno I'm using is quite pessimistic compared to most. As I'm sure you all understand, it's the shape of the graph and the changes to its shape as modifications are made that's useful, rather than peak values. The dotted line is prior to the header and midpipe upgrades, meaning stock other than a MS intake and BHR ignition along with fresh spark plugs and 5w30 Q motor oil.

http://i259.photobucket.com/albums/hh314/Modified_Dave/catvsstock.jpg

I briefly plugged in the AccessPORT to take a peek at the AFRs, ignition timing and injector duty cycle and everything looked good and normal there, but I'll post the data logs when I get a chance. I also checked the vacuum system and the 3-stage intake and everything appears to be in good shape there. I haven't had a proper compression test done though, so I guess that may be the next step. I've been holding off on that one since I don't want to pay the local stealership the $240 they want to charge me to bust out their fancy rotary compression tester.

NYC Drift King, I think the BC coilovers are a very suitable street setup. The ride quality with their off-the-shelf spring rates is really quite good and at 8/10th driving at the track they work well. It's when you're really pushing hard at the track that I've had rear shock travel issues as well as a need for better roll control in general. So I may switch to a more motorsports oriented setup, most likely Moton Clubsports since I've had a lot of success with the Moton triples on my racecar and am well versed in dialling these dampers in for best performance.

kjchristopher, I believe the welded OEM pedal BHR offers is STX legal but those bolt-in pedal braces are not. Am I wrong on this? It's still just an OEM pedal, so I can't see how/why it'd be outside the rules for STX to weld areas that simply secure the two halves of the pedal assembly together in a superior way to the factory tack welds. The pump is another issue, but I swapped that in as part of my continued exploration of why my engine is making poor power up top. It's a 10 minute job to swap the OEM pump back in, so I'm not too concerned about that one. Any news on the legality of the rear wing for STX next year?

And remember kids, it's better to look fast than to be fast ;)

http://i259.photobucket.com/albums/hh314/Modified_Dave/rx8rig1sm.jpg

kjchristopher, I believe the welded OEM pedal BHR offers is STX legal but those bolt-in pedal braces are not. Am I wrong on this? It's still just an OEM pedal, so I can't see how/why it'd be outside the rules for STX to weld areas that simply secure the two halves of the pedal assembly together in a superior way to the factory tack welds.

There isn't an allowance for

reinforcement-weld the backplate and mainframe to eliminate the longitudinal stresses which causes the separation between the mainframe and backplate

in the ST rule set.

You really can't look at the rules in the mindset described. You have to take a "where does it say I can" approach. In your case, you need to find a rule you can point to that would allow extra welding and reinforcement. If it mentioned the pedal, that would be the cat's meow.

Here is what I would call a typical RX8 dyno on a healthy engine with new plugs and coils .
Right up until 7000 rpm the power is pretty much identical . After that yours is dipping away vs a good dyno which improves 10-15 whp from that point . So you are at least 15whp down across the meat of the power band .
Have you adjusted Dwell for the BHR coils ? Are you connections all good ? What do your AFRs look like past 7000 ?


http://www.rx8club.com/attachment.php?attachmentid=134450&stc=1&d=1236029552

Any news on the legality of the rear wing for STX next year?
Per one of the recent Fastracks, earliest any changes to the wings and body kits in ST will go into effect is 1/1/2012. So things will remain status quo in 2011.

Looking forward to the rest of the articles - been following the build in the mag.

S

Here is what I would call a typical RX8 dyne

typical fail maybe, otherwise not even close ....

typical fail maybe, otherwise not even close ....

Really ? Pretty much all the stock dynos iv'e seen fall into the range between 165-185whp . which forum have you been reading ?

There isn't an allowance for in the ST rule set.

You really can't look at the rules in the mindset described. You have to take a "where does it say I can" approach. In your case, you need to find a rule you can point to that would allow extra welding and reinforcement. If it mentioned the pedal, that would be the cat's meow.

I like your note about the reason you edited your post. I appreciate you going easy on me. If I've gotta swap the unwelded stock pedal back in for STX events, so be it. It's actually a very easy job. Three nuts and a couple wiring harness plugs. In any case, since I also use the car for Time Attack events, I'm very happy to have the stronger clutch pedal for that purpose, particularly since I've been chasing a 3rd to 4th gear shifting problem at high rpm and one theory was a flexing clutch pedal causing poor clutch engagement/disengagement.

Brettus: agreed, it does seem like my graph is still not climbing the way it should on that final of the three humps. I haven't adjusted the dwell yet. That'll happen when we do the full retune using the AP. AFRs in the top end were in the 11's and dropped to about 11.2 by redline. If memory serves ignition timing climbed to about 29-30.

chiketkd, cool thanks for the update on that. Glad to hear I should be able to run the wing I recently picked up from wingshop.co.uk. It's a pretty sexy piece of carbon.

Thanks guys. Any of you going to SEMA? Would love to meet some of you rotards and coneheads in person.

Oh btw, that martini shaker cat lost zero hp compared to the resonated catless midpipe. Actually, it gained a bit of power with the martini shaker, but that was probably just because engine temps were a bit lower than the dyno runs done with the catless midpipe. Still, pretty amazing for a HFC to rob zero power while being proven not to throw any CELs. Gotta thank TeamRX8 for tipping his hand on this part and for Milltek supplying it to me at a very fair price.

http://i259.photobucket.com/albums/hh314/Modified_Dave/martinishaker.jpg

Another thing that surprised me was how white the o2 sensors and exhaust port looked when swapping the header and midpipe. Even on the most aggressively tuned NA piston engines I've run, with AFRs in the mid to high 13's, I've never seen exhaust ports this color. Is this normal for a Renesis?

http://i259.photobucket.com/albums/hh314/Modified_Dave/exhaustport.jpg
http://i259.photobucket.com/albums/hh314/Modified_Dave/02sensor.jpg

If I've gotta swap the unwelded stock pedal back in for STX events, so be it. It's actually a very easy job. Three nuts and a couple wiring harness plugs. In any case, since I also use the car for Time Attack events, I'm very happy to have the stronger clutch pedal for that purpose, particularly since I've been chasing a 3rd to 4th gear shifting problem at high rpm and one theory was a flexing clutch pedal causing poor clutch engagement/disengagement.

I've been following the clutch pedal issue for three years now, and I'm convinced the failure is because people unintentionally push the pedal sideways as they push it in. The sideways forces are what cause it to fail. I sit closer than most people do and so tend to push the pedal straight on the plane it pivots on. I've been tracking and autocrossing my 8 pretty hard since I got it (and daily-driving), and check the clutch assembly before and after each event. No significant side-to-side play or and no visible tears in the metal or welds. So do what you can to push the pedal straight in with no side-to-side force and it should last just fine during your STX events. :)

typical fail maybe, otherwise not even close ....

OK Mr. seagull poster, how about posting up what you think a non-"fail" dyno looks like?

This was Team's STU Cobb dyno from a few years ago.

^ that was in 2007, not so special now ....

sub'd can't wait to read the nov issue

Dave does the ARK operate via OBD II or is it a direct plugin? I've been looking for a replacement for the MSD DashHawk for a while now but haven't found anything that I liked.

I looked up the MFD after seeing it in the latest Modified. Looks like they make an MFD2 that does the same stuff as the MFD, but also connects to the OBD port. Check it out:

http://www.arkdesign-us.com/mfd2-multi-function-dash-2

Ok, I read other magazines too... In the Nov Grass Roots Motorsports on Page 122 of the article on an MX-5, they say "Our experience with the RX-8 and later Miatas has taught us that too much negative camber at the rear end actually binds up the car, so we set the rear suspension to -1.5 degrees..."

When I had my used KW3s installed, I had them set it to -2 all around and have been happy, but I have only had one track event to really try it out. Do others know what they are talking about?

They also put a big sway bar on the front of the MX5 and none on the rear. This sounds like an Rx (I mean prescription) for a lot of understeer, but I am the rookie here.

I posted on GRM too. Per Schroeder replied with "Bind-up is referring to too much rear grip---to the point where the car feels pushy or tight as it's understeering." I don't know if they had a big sway on the front of the RX-8, why not run less bar on the front rather than reducing grip at the rear?

Sure, if you want it to roll over in the corners like a pig in the mud

I posted on GRM too. Per Schroeder replied with "Bind-up is referring to too much rear grip---to the point where the car feels pushy or tight as it's understeering." I don't know if they had a big sway on the front of the RX-8, why not run less bar on the front rather than reducing grip at the rear?
You're asking some good questions...

However, someone giving you the answer is not going to be as meaningful/rewarding as you finding it out yourself. Read books on setting up race cars, test different springs, shock settings, swaybars, alignments, ride heights etc on your car. See what works and what fails horribly. Develop as a driver. Develop your car. In the end, you'll draw your own conclusions and be the wiser for it.

Subscribed

Ok, I read other magazines too... In the Nov Grass Roots Motorsports on Page 122 of the article on an MX-5, they say "Our experience with the RX-8 and later Miatas has taught us that too much negative camber at the rear end actually binds up the car, so we set the rear suspension to -1.5 degrees..."

When I had my used KW3s installed, I had them set it to -2 all around and have been happy, but I have only had one track event to really try it out. Do others know what they are talking about?

They also put a big sway bar on the front of the MX5 and none on the rear. This sounds like and RX (I mean prescription) for a lot of understeer, but I am the rookie here.

Interesting stuff, ganseg. I've done some work for GRM in the past. Great guys and a great mag. I read it every month and have been for the last decade or so.

Regarding the rear wheel camber issue GRM raised, I'm not sure if the car in question was using race shocks and springs, nor do I know their toe settings or tire choice, so it's difficult to comment on that. But since we know the rear of these cars (both the Miata and the RX-8) gain camber quite aggressively during rear suspension compression, it does make sense to run less static negative camber. I think their -1.5 degrees of rear camber is a good starting point, from which you can dial in your own settings using a tire pyrometer to see how much of the contact patch you're really using. Ideally you want to see about 10 degrees more tire temp on the inner third of the contact patch with the tire running in its optimum temp range right across the board.

With respect to running a big front sway bar and no rear bar, understeer is caused when you have more rear grip than front grip and this front/rear grip balance is affected by much more than just sway bars. Front and rear spring rates and damper settings as well as wheel alignment (both camber and toe) also play a big roll, as does weight distribution and even front/rear downforce when running at higher speed circuits. In the case of my RX-8 on BC coilovers w/ stock sway bars, the only way I've been able to dial out the excessive oversteer it's been suffering from during track testing is to disconnect the rear bar and increase the spring rates, add some preload, and dial in a little extra rear toe-in, but ultimately the inconsistent rear grip issue I've been struggling with has to do with rear suspension travel rather than front/rear roll stiffness. So take my setup with a grain of salt, but it does illustrate the fact that running with the rear bar disconnected doesn't necessarily mean understeer-city.

Coincidentally I've recently been discussing suspension design and sway bar tuning with Peter Cambridge, formerly the senior chassis development engineer for Prodrive and the man responsible for developing their RX-8 demo car and their PZ-type suspension kit for it. During our discussions, I mentioned to him how my RX-8 was generating much better rear grip and overall balance with the rear sway bar disconnected. He responded that when he was working on the Aston Martin road suspension he had a long chat with George Howard-Chappel who runs the Prodrive race team and that in his view traction is everything, so they did not run a rear sway bar on their race cars. They also did not run tender springs on the rear, just a single main spring that they let go free in extreme rebound.

Of course Prodrive would have had the rest of their suspension package carefully dialled in to work with no rear bar, so don't think that disconnecting yours will magically make the car handle like a Prodrive racecar. It's simply an indication that there's more than one way to dial in a suspension, and how you dial it in will depend on the tracks you're racing at as well as your driving style. At high speed circuits I always disconnect the rear bar on my race car because I prefer the car to have a bit of understeer at the limit, which allows me to drive into corners more aggressively and confidently and then I get it to turn with trail braking and throttle modulation. But other guys in similar cars run a rear bar because they like a looser setup. For autocross, which is a totally different animal, I'm much more interested in transitional response and low speed rotation, so well matched sway bars with some added rear stiffness is what works best for me (along with different alignment settings and tire pressures and damper settings). I haven't done much autocrossing in the 8 yet, so time will tell what works best for me in this car when dodging cones.

If you are making an RX-8 work without a rear swaybar it's only because you're masking some bigger setup problem.

Ok, I read other magazines too... In the Nov Grass Roots Motorsports on Page 122 of the article on an MX-5, they say "Our experience with the RX-8 and later Miatas has taught us that too much negative camber at the rear end actually binds up the car, so we set the rear suspension to -1.5 degrees..."

When I had my used KW3s installed, I had them set it to -2 all around and have been happy, but I have only had one track event to really try it out. Do others know what they are talking about?

They also put a big sway bar on the front of the MX5 and none on the rear. This sounds like and RX (I mean prescription) for a lot of understeer, but I am the rookie here.

The reference in the article was directly related to our experience setting up my past SCCA Stock class Solo cars over the last 12 years. The RX8 we were referring to in the article was running under stock class rules which requires stock springs and stock rear bar. The front bar, alignment and air pressure are your main tuning tools in this class.

The "binding-up" comment was referencing throttle induced understeer from apex to trackout using Hoosier A6's which have a lot more longitudinal grip (forward bite) than 140+ treadwear tires when warm. The power-on understeer was the overriding handling trait that we worked to correct during the three years John Rogers and I competed in B-stock with the car. We had to balance this trait against transitional oversteer at the limit when hammering through slaloms etc.

We found adding a slightly stiffer front bar (Hotchkis MX5 bar) coupled with reduced negative rear camber struck a balance we were happy with on most autocross courses. Our tire temps and shoulder wear also confirmed that the set-up was in a "happy place". Another consideration was the ProSolo drag-style launch. Adding unneeded rear negative camber would hurt 60 ft times.

Since you are running KW's, 140+ tread wear tires and tracking the car, your optimum set-up is going to vary from ours. Hope this clears things up a bit.

Chris Harvey
GRM/Tire Rack MX5 STR

PS - The only time we removed the rear bar from the STR MX5 was during anti-roll bar back to back testing. We found no time benefit or significant improvement in handling balance although the drivers could feel the balance shift slightly. Most of the season was run with the rear Hotchkis bar set in the "soft" setting.

Dave and Zoom4Three, thanks for your thorough and thoughtful responses! I am genuinely interested in this and have read several books (Carroll Smith, Ross Bentley) and experimented with my cars. Unfortunatley this has to be within a limited budget of time and money, so hearing other's experience is huge. I get about one or two track weekends a year and have driven on four tracks with about 12 events total. Thankfully my current setup is good for the two high-speed tracks (Brainerd long course and Road America), but I want to experiment with less understeer for the more technical tracks. When I go to a more technical track, I may lower my rear neg camber a bit to see if I can "handle" it! Right now it understeers more than stock but that gives me a comfort zone in the 70+ mph corners on the faster tracks I drive. (I think my front spring rate is 450# and my rear is 285#. ( Stock sways, nt01s, track pads, -2 camber and slight toe in all around.)

If you are making an RX-8 work without a rear swaybar it's only because you're masking some bigger setup problem.

100% agree. I am trying to work around the stock front bar and rear travel limitations at the moment. I hope to make a decent size adjustable rear bar work with the Moton Clubsports and a big adjustable front bar. Work in progress, as always.

INPUT!

Here's a direct answer from John Rogers at The Tire Rack--even more info for you.




Gary:

Let me set this up a little more. Our experience was based on the Miata/RX-8 competing in SCCA "stock" class autocross, which used stock springs rates, aftermarket dampers, larger front anti-roll bar and stock rear bar. We maxed out the front negative camber, which usually landed around -1.4 to -1.5 degrees per side. Our early attempts at alignment set the rear to match whatever we could get in the front. But ultimately we found the car had some steady-state understeer. The rear had too much lateral grip relative to the front, resulting in insufficient yaw rate. Some slip angle is needed for the tire to generate significant cornering force, and the highest ultimate cornering power comes when there is a few degrees of yaw at the rear of the car.

We ultimately found that reducing the negative camber at the rear by about half a degree versus the front took away a little ultimate lateral grip at the rear. Just enough to allow the rear to yaw a few degrees, which helped the car to rotate (even at steady state). Cornering speed increased, and ultimately allowed the driver to unwind the wheel and pick up the throttle sooner since he wasn’t waiting on the gentle push of the front tires. We had also played with the rear toe setting, but found going beyond zero toe would make the car too loose in transitions, so we returned it to zero. Backing off the rear negative camber proved to strike the best balance between steady state and transition handling.

Admittedly, using the KW coilovers on your RX-8 brings another variable to the equation that we didn’t face with our “stock” Miata or RX-8. KW changes spring rates. The stock springs on the Miata and RX-8 are relatively soft, especially in the rear. I haven’t checked the progressive rate of the rear springs, but I suspect that KW increases the rear rates a little more than the front. This effectively moves work off the front to the rear, helping solve the understeer problem. So it’s possible that there is less need to reduce rear negative camber than in our “stock” car. As we put this project together we decided to start with something (the alignment) we know, measure and tune from there. During our testing for this project, we compared the OE suspension with the KW coilovers, leaving the Mazda anti-roll bars on the car. In this configuration, we found the balance of our MX-5 to be pretty good, even with the approx. ½ degree front to rear stagger in negative camber.

I’m not sure if you have changed the anti-roll bars on your RX-8. But for this project it was only with the addition of the larger anti-roll bars that we found a need to tweak our alignment set up further. But as far as steady-state cornering goes, the small stagger in negative camber continues to work well. There is no shortage of rear traction during cornering, and steady-state understeer is almost non-existent. We have had to add in a little rear toe in to solve a power-on oversteer issue. But I suspect we’re now cornering and accelerating hard enough that there is some additional bushing flex causing dome dynamic alignment changes, etc.

That input was posted here many years ago, forever buried in the annals of the RX8Club archives ... I suppose since it didnt get posted with any association to TR or GRM it lacked the ZOMG factor :hahano:

Sub...

under my skin is right. If you take 10% of the time you and a few others spend degrading posts and put some of your good input into posts instead, we all would be far ahead. I am not an idiot just asking random questions and bothering people. I want to learn and maybe others will learn at the same time. Three or four people made the effort in the last 24 hours to be helpful. If I had searched, I would not have gotten back to what you learned 4 years ago.

When I want to enjoy my time online, i have to go elsewhere. Sadly I have to read thru all the lambasts here to get to the worthwhile stuff.

I never said you were, that's all in your head

I'll change that to "under your oversensitive skin", thanks

You can go somewhere else if it makes you happy, but you will never find the wealth of RX-8 information that already exists here

you will never find the wealth of RX-8 information that already exists here

I agree. Why don't we improve on it instead of taking away from it? When I had an MR-2 spyder, same situation on spyderchat only worse. Everyone who would post their car for sale would get squatted on. Nearly every new person would get squatted on. The site had great info, and again it was the only one. But it was painful reading it, not funny.

I don't want a site where everyone just asks without engaging their brain. I do want a site where people are decent to each other and support each other. I also wouldn't mind having more people become interested in the 8. That will help availability of parts and prices. Maybe the 8 wouldn't be on the chopping block.

I know you have a lot to offer. I know this site has a lot of great info. The year I have had with the RX-8 has been one of the most fun I have had with a car and this site has made a huge difference. This thread is really cool. What is there to be negative about?

That's an interesting read from John at TR. Thanks for adding it to the thread, ganseg.

Here's a surprising tidbit of info from Peter Cambridge, the former Prodrive suspension guru I mentioned earlier. While developing the Prodrive shock/spring package for the RX-8, Mazda Japan sent him a lot of information about the car, some of which he couldn't share with me but their recommended alignment settings for track use struck me as quite surprising, especially in light of the GRM/TR method of setting up their stock class Miata (though that's an autocross setup, which tend to be quite different from race track setups).

According to Peter, "At a trim height of 355mm front and rear (15mm lower than standard UK car), from the wheel centre to arch lip:

Front
Total toe 10' in
Camber -1deg 45'
Caster 7deg 41'

Rear
Total toe 30' in
Camber -2deg 00'

These settings assume the car is running stock 18" Bridgestone tyres."

Toe-in on the front is not something I was expecting to see, nor the aggressive toe-in on the rear or the fact that they've recommended more rear negative camber than front. All I can assume is that they've found these settings to work best with the relatively narrow OEM Bridgestones at whatever race track they do their testing at, whereas we're all accustomed to setting our cars up for considerably wider and/or stickier tires with big front sway bars.

Still, I thought this was worth sharing if for no other reason than to illustrate the fact that there's a wide range of suspension setups that can be made to work, so it's really up to each of us to acquire the necessary tools to dial ours in for best performance for our particular set of modifications, driving style, and type of driving (autocross, HPDE, RR, drift, etc). I never head to the track without a tire pressure gauge, tire pyrometer, camber gauge and toe plates, a lap timer/data acquisition system (I've mostly been using a Vbox Driftbox for it's ease of use and yaw sensor), and a laptop to record all my settings and changes to them. Keeping good records really does help a lot when trying to dial in a suspension, not to mention it can save you some work when you go back to the same track but don't remember what your dampers were set at or what sway bar stiffness worked best.

we at the Ga RX8 club have literally thousands of miles on track. Well over a combined 50,000 during the past 6 years. One members car has 7-8K on track and over 100K on the oridginal engine.
One member, if I am not mistaken, is currently in the lead for TTD with NASA SE.
We run Road Atlanta, Roebling Road, CMP, Barber in Birmingham, etc.
We have tried many different suspension set ups and alignment settings.
Wide variety--from oem to anything goes.
Currently mine ( I have a little over 300hp to the wheels)
Kw's
RB front and rear bars and front end links
running 18x9.5 rpf 1 wheel with" R6 245/35/18's
-1.7 up front
-1.5 in rear
minimum toe in front and rear
cant remember the castor
Lets just say the car is much more capable than I am. It is very confidence inspiring.
Transistions are beatiful--not only in the esses but in braking to throttle and throttle to braking all in the same turn.
By the way I am oem on the body--no spoilers or lips.
Hard fast line braking is among the best and trailbraking I think IS the best. So after years of driving, this is the set up I have settled for.
Now like others have said---you have to do your own homework in your own car. No substitute.
And here is my point --In our club--- no two cars have the same set up--none. Wonder why?
And now I have to get on a John Deer tractor and suck up leaves---sigh.
OD

olddragger, so you're running some front toe-in? Very interesting. I tend to dial in some front toe-out on just about any car I take to the track as a way of aiding turn-in response, but maybe turn-in response is already so good on the 8 that I've gone in the wrong direction here. I assume you're using the toe-in to help with high speed stability, given that you're running at some high speed circuits?

Road Atlanta = pure awesomeness, btw. That is a big boys track if there ever was one. You've got some great road courses down there in the duuurty south :) And it would appear I only have 7100 posts to catch up to you. Heh.

Lol---thanks Dude and yes high speed stability is my preference. With my Fi set up i am seeing fairly high speeds (Approx 140+ or so) so braking and high speed maneuvering is not to be ignored by someone wearing bifocals.
I have never had a need for more turn in--the 8 is so dang smooth and with trail braking ( one of the great under recognized strengths of this car) a twitchy sudden turn in response was not for me. I end up steering with a lot more than the steering wheel :)
I have seen these discussions time after time and mostly really good advice is given, but, rarely do I see the suspension mentioned in dealing with lift throttle, throttle manipulation during steady state cornering, rapid throttle on/brake on episodes, rapid chassis recovery or uneven surfaces. Thats real life on the track and very important as you know.
I am sure you also know that anything can happen-- and you have to drive the piece of track you are given
My point being --whether you are at a 1.7 or a 2.0 chamber-- if everything else is ok then it is not going to matter much at all. The most important thing IMHO is getting used to the car and being honest about your driving style/ability. More times than not its the driver that makes the difference not minor changes to suspension settings.

Good luck on your adventure dude--i will be envious and following along vacariously
OD

Dave, forgive me if it's in the thread or the magazine (I've read both) but a couple of quick questions regarding the ARK MFD.
I've been looking for a neat way to integrate proper water temp, oil temp and oil pressure for a while. I have the Racing Beat pod, but haven't bought any gauges yet (in next seasons budget.) but I don't like the idea of losing that space (it's where i keep my parking pass for work) so was intrigued by the neat all-in-oneness of the ARK unit.
So, the questions:
1) Have you done any testing on the accuracy of their senders? I've seen some manufacturers seem to be all over the map.
2) While it looks small, how big is the display unit really, and how many places in the cabin would it fit? I'm trying to keep a fairly stock look to my cabin (thus the Racing Beat pod) but not sure I like the stuck on the back of the ashtray lid thing, but can't figure out if it would fit elsewhere in the cabin relatively neatly but still visible.

Have you seen this:
http://www.rx8club.com/showthread.php?p=3762549#post3762549

I've looked at the GOODBox and think it's an awesome little device, but I just can't get over not being able to see more than 2 gauges at once.
I'm used to my race car which is instrumented like an airplane (Tach, voltage, oil temp, oil pressure, water temp, A/F for each rotor and EGT for each rotor) so I feel a bit under-informed just adding 3 gauges to the RX8, but I want to keep as clean and stock looking of an interior as possible.
The GOODBox checks that box huge, but is just a touch too limited in what it can display. I'm hoping this ARK MFD might be an acceptable middle ground.

Hey Redshift. The ARK MFD is about the size of a credit card, maybe slightly larger but not by much. It's approx a half inch thick, so all in all a very compact display that you can easily mount in a variety of places.

I chose to mount mine on the front of the cigarette tray, since I don't smoke. This allowed me to easily run the wiring in from behind, and I just drilled one small hole through the tray face to fish the wire thru to the display. The display is held on with adhesive backed velcro, so it's super easy to remove if I was ever worried about being parked somewhere where it might attract thieves, but it's such a small display I don't think too many people would even notice it.

It'll display up to three gauges (in either digital or dial style readout) on a single screen, but you can easily scroll to the next screen for addition data readouts. I haven't figured out how to switch the readouts from C to F yet, but presumably that can be done. Not really an issue for me since I live in Canada where we use the metric system, but being able to read temps in F would be nice too so I'll have to see if I can figure out if the unit can switch back and forth between these units of measure.

I haven't tested the sending units for accuracy. I think they're Bosch, so I have no reason to doubt their reliability. Being able to see an actual temp and pressure readout for oil and water is a huge step up from the OEM gauges not to mention they're much more responsive (OEM water and oil gauges always lag way behind realtime temps/pressures), and given how simple a device these sending units are I'm sure they must be quite accurate.

Excellent response. Thanks Dave! I'm in Canada as well so I'm cool with Metric. My race car is all in F, but I'm familiar enough with metric that it's not a huge problem.
I'm assuming it's clear/bright enough that you can read it down on the ashtray door? (I actually pulled my ashtray out the day I got the car.. made it just the right size for my parking pass to squeeze in)

Seems like a very interesting option. My inner gadget geek loves it. If I decide to go that way, I'll just need to figure out a decent way to source it in Canada without getting "brokeraged" too badly...

The display is plenty bright. It's easy to read it day or night, direct light or not.

I find if parts are shipped from the States using USPS Ground the brokerage fees are considerably lower than if one of the big courier companies are used. Both UPS and FedEx are really inconsistent with their brokerage...sometimes they charge a pretty reasonable rate and other times it's just completely out of line expensive. The other option I use is to ship just across the border to Niagara Falls, NY and then I go pick up the package myself, but the commute from Halifax to Niagara Falls may make that a bit impractical for you and I hear the swim across the Bay of Fundy isn't all that much fun...dee :)

I guess you must do most of your racing at AMP? I've been racing here in Ontario for a lot of years but have always wanted to make the trip out to your neck of the woods to check out AMP and do Targa NF (not that NF is really your neck of the woods, but you're a lot closer to The Rock than I am).

Yeah the commute to the boarder is a bit far for me. FedEx hasn't been too bad, but UPS kill me. I've shipped enough stuff USPS that when I was building my RX7 the people who worked the counter at the post office knew me on sight and I didn't even need to show them my paperwork. The would see me come in the front door and just go out back and get my package before I even got to the counter.
Unfortunately MazdaSpeed Motorsports has started shipping UPS only to Canada. I used to buy a ton of stuff from them.

And yes, you've got it. AMP is my home track. I only live about 30 minutes away. If you ever plan to come down, drop me a line. We can usually find a bed for a racer from away. We just had our season-ending steal-of-a-deal fundraiser non-points race. 3 hour enduro, morning practice and pot-luck lunch for a $100 per car entry fee. As many drives as you want. We had a team come down from Toronto for it this year. Had two spec-Miata's from the US come up last year. They planned to come this year as well, but apparently one wrecked and was still healing.
It really is a little jewel of a track. So technical. Everybody who runs it that isn't just straight-line obsessed (it doesn't have any straight) loves the track. I didn't get out at all this year as life got in the way, and I'm kind of craving a few laps right now. Kitchen renovations + better half between jobs + catastrophic engine failure on the FC at the Canadian Solosprint Nationals last year does not equal budget or time to run this year.

We hosted the Nationals at AMP last year, and I was on the organizing team. I only ran the car on a whim since I was going to be at the track all day yesterday. Turned into an expensive whim.

I haven't made it over to Targa yet. No budget to run it, but I've wanted to volunteer. Unfortunately September is always a busy month for me. A lot of folks I know locally participate and have some great stories.


*Edit: BTW, to go back to your automotive race roots, there is a steal of a deal on a Targa spec Integra right now. Friend of mine from work co-drove it for a few years, then he bowed out and the other guy has been running it with his son. They've gone WRX now and are pretty much giving a class-competitive, and sorted, proven finisher, away.

Sucks that MS is shipping via UPS now. That really hurts the savings that program offers.

I'll definitely let you know if I make it out to AMP. Happy to reciprocate the offer of finding you a place to stay if you ever make it to Ontario for some racing. Sorry to hear about you losing a motor at the SoloSprint Nationals. We seem to live parallel lives, because I actually helped organize the first SoloSprint Nationals back in '05 or '06 at Shannonville Motorsports Park here in Ontario, though I had better luck than you as a competitor (drove a friend's CRX and won my class and the overall championship).

If I do Targa, it'll be in a car I build for the magazine as a project specifically for that event. The last 2 years I've had deals with major automakers fall thru at the last second, both times due to corporate level drama (one VP approved it, another didn't, pissing contest ensured kind of thing). So frustrating. But one of these years I'll get a deal done and have a car and budget to build it for the event. Maybe I should try for a Mazda2 for 2011 :)

I agree. FedEx is faster and better all around. UPS Ground sucks teh big one.

Oops, there I go with the negative vibes again .... :hahano:

I think a Mazda2 would be perfect! One of the charter members of AMP (it's still a volunteer run and club owned track) did Targa in a Toyota Echo a couple of years ago. His co-driver was the guy who runs SpeedSport, which is the biggest car show on the east coast.
They nicknamed it "Timmy the Turtle" and had turtle graphics on the side.
He rolled it the first day the first year. Took it home, took the cage out, and his son daily drove it for the next year, dents and all. Next year, put the cage back in, took the dents out, and ran it again and finished that year. We had his 70th birthday at the track for him last year, and he and his son co-drove (and won with) his Datsun 510.

Anyway, enough internet racing (stupid winter) and back to your project car. :)

Everyone here at Black Halo Racing just wanted to say thanks to Dave for this month's article and we're excited to see the project RX8 develop!

Be sure to check out my post regarding this article here: http://www.rx8club.com/showpost.php?p=3788864&postcount=9

Dave , curious to know if you ever resolved the high rpm hp dropoff issue ?

Dave , curious to know if you ever resolved the high rpm hp dropoff issue ?

Not yet, Brettus. I'm going to have a proper compression test done, since my latest theory is carbon buildup on the apex seals. I actually picked up a spare engine and trans since my trans is in rough shape, so I'm now planning to blueprint and balance the engine over the winter and swap it in. If I want to be even remotely competitive in STX (or SM if I decide to go nuts on the modifications) I'll need a healthy engine, plus I think it'll make for a cool tech story to do a rebuild.

Flashwing, thanks man. I should add that although I reported in the story that the ENEOS trans oil didn't do much to help the 4th gear engagement problem, with this oil 4th gear is now only sticking before engaging, when it was grinding badly with the OEM fluid. So the ENOES oil has made a real difference, but I know the problem is still there so I'll be putting a freshly rebuilt trans in over the winter.

This good story line will keep me buying the magazine. This has been great fun. Have you read the book Street Rotary by Mark Warner that was brought up in the BHR tread? I am asking for it for Christmas.

Updates??? Just read jan 2011 issue. Installed: RB headers and RB modified duel res test pipe.

He keeps us hanging every month! I am taking guesses of where the top end went. My guess is low compression.

If that is true, I would think it would be better to test the compression before tuning...

Jr mechanic out...

This good story line will keep me buying the magazine. This has been great fun. Have you read the book Street Rotary by Mark Warner that was brought up in the BHR tread? I am asking for it for Christmas.

I have read Street Rotary, great book. I was a little disappointed to see the dyno results in the issue of Modified. 160HP? I am looking forward to reading the compression test results and the engine rebuild articles. I may just have to renew my Modified subscription now.

I have read Street Rotary, great book. I was a little disappointed to see the dyno results in the issue of Modified. 160HP? I am looking forward to reading the compression test results and the engine rebuild articles. I may just have to renew my Modified subscription now.

In the Jan issue, it pulls 170 hp with the header and high flow cat. So what is your guess on the issue?

The Jan issue has a request for people to submit info about their cars. I think we should flood them with RX-8 letters!

In the Jan issue, it pulls 170 hp with the header and high flow cat. So what is your guess on the issue?

The Jan issue has a request for people to submit info about their cars. I think we should flood them with RX-8 letters!


Meh, with all of his mods he would be pushing 190HP+ easy on a properly balanced, clearance d, rebuild. Where do we send our letters? I have some new pics of my nitrous setup :) I have most of the BHR equipment as well :lol:

Hey guys. Sorry to leave you hanging. Been super busy with a couple of other projects the last few weeks, but I just had a compression test done and here are the results.

With the engine fully warmed up, Rob the Master Tech at my local Mazda dealership (Mountain Mazda, in Hamilton, Ontario, Canada) hooked up his super duper compression tester that's linked to a customized computer station. I was expecting him to use the usual rotary three stage compression tester, but with this system the compression data goes right to his computer screen, which is pretty cool. Here's what it looks like.

http://i259.photobucket.com/albums/hh314/Modified_Dave/TechStation.jpg
http://i259.photobucket.com/albums/hh314/Modified_Dave/CompressionTest1.jpg

As you can see, things weren't looking too good when testing Rotor 1. It showed zero compression on chamber 3, but that was a bit puzzling because the Tech felt the engine would be running a lot rougher if the engine truly had zero compression on that chamber. Plus you'll notice the engine speed was only 82 RPM when for testing purposes the standard is 250 RPM.

So we retested Rotor 1 and tested Rotor 2 and the results looked a fair bit better.

http://i259.photobucket.com/albums/hh314/Modified_Dave/CompressionTest2.jpg

FYI, the standards for compression, as taken from the factory printout the Tech gave me, are 830 kPa (or 120 psi) with a minimum acceptable readout of 680 kPa (or 98.6 psi). As you can see, my engine falls well below the standard of 830 kPa but a bit above the minimum acceptable reading. It's also worth noting that variation between chambers is well within spec, since the standard/minimum acceptable difference is 150 kPa (21.8 psi)/100 kPa (14.5 psi).

The confusing part is how/why we got that zero compression reading on Chamber 3 of Rotor 1 the first time we tested it. The Tech felt perhaps there was some carbon in the chamber that's prevented the apex seal from sealing properly but then came free on the subsequent tests. He's recommended I give the engine a good cleaning to try to clear out as much carbon as possible, at which point we'll redo the test.

While looking at all the sensor data while it was hooked up to this uber computer station, we also noticed the MAF sensor was reading a little on the low side at any given RPM. So I'm going to give it a good cleaning too, though perhaps the low readings were a function of the Mazdaspeed CAI?

We also saw a fairly consistent jumping and falling of the secondary o2 sensor voltage, which the Tech felt was being caused by the exhaust mods but I'm thinking maybe the sensor needs to be replaced. Thoughts?

Anyway, since I have a spare engine and trans that I plan to rebuild this winter, and seeing that this engine is definitely on the low side with respect to compression, I'm definitely going to go ahead with a proper blueprint and balance of the spare engine and then swap it in and finally have Jeff from MM do his thing with the AccessPORT. I don't think there's much point in tuning the ECU until after I get a fresh engine in the car, though perhaps Jeff will want to see how much he can help the top end on the current engine before I swap in the new one, just as an experiment in tuning. Might be worth the effort, but that's something I'll have to discuss with him.

Oh, here's one of the printouts I got from the Tech, which shows things are more or less within spec with most of the sensor readouts, though the Purge Flow Monitor reading is getting very close to the max end of the acceptable range, so I should probably clean the Evap system while I'm at it. But at least we're not seeing a lot of misfires and the HJS cat doesn't seem to be freaking out the o2 sensors which is great to see.

http://i259.photobucket.com/albums/hh314/Modified_Dave/EngineData1.jpg

Anyway, that's where things are at for the moment. I'm going to be working with Joe Furgeson from RPM on the engine rebuild, and if I decide to skip the STX plans and move up to a less limiting class then we'll also port the engine and may look at aftermarket seals in preparation for boooooost :) We'll see.

I have been reading the articles... Love what you are doing :)

Hmmm still in spec but down 20HP (give or take)? Thanks for sharing I look forward to following this.

Boooost......MMmmmmmm.

http://www.atpturbo.com/mm5/graphics/00000001/Catalog%20Images/Turbochargers/GT28RS-375375.jpg

http://forums.pelicanparts.com/uploads9/homer_drooling1167490322.jpg

probably lost tbe side seal(s) on that rotor/chamber

pull the crankcase vent tubes from the intake, plug
everything but one tube, and install a blowby flowmeter on that tube, should pretty much confirm it under a loaded WOT run

and have a lot of rags and degreaser on standby. lol.
OD

probably lost tbe side seal(s) on that rotor/chamber

pull the crankcase vent tubes from the intake, plug
everything but one tube, and install a blowby flowmeter on that tube, should pretty much confirm it under a loaded WOT run

Cool, thanks Team. Will definitely give that a try and report back on the results.

Where do we send our letters? I have some new pics of my nitrous setup :) I have most of the BHR equipment as well :lol:

That would be cool to submit. Here is the info from page 10 of the mag:

Hi-res pics (at least 1mb/300 dpi in size)
"Include a spec sheet of all mods" in the following format:
Car year and model
Engine mods
Wheels, brakes and suspension mods
Exterior mods
Interior mods
Power Output (leave blank if you don't know)
Why you chose it. Add any details that didn't fit into the spec sheet.
Full name and contact info
Send to Peter@modified.com