Racing the RX-8
 

Hello fellow racers. My name is Sam Harris. I've been racing for 11 yrs in everything from BMWs to Miatas to Porsches to Hondas. I noticed that RX-8s swept PTD at Nationals this year but no one is running an RX-8 in TTD. I've instructed people with RX-8s and driven a few on the street but never owned one. They seem to handle like a mid-engined car... easy to rotate (which I love).

Anyway, I've been thinking about fielding an RX-8 in NASA TTD this season. I've tried searching these forums, but the search feature doesn't allow searching for multiple terms. It just seems to be equipped to "or" not "and" all parameters. This makes it exceedingly difficult to find threads like, "Year to avoid" or "Common problems with tracking." Every car has its quirks... Porsches blow power steering pumps if you don't insulate the return line. Every car has its secrets... Miatas are faster with narrower tires because the decreased rolling resistance more than makes up for loss in lateral traction. There are a thousand little tidbits that you only know if you've logged the laps.

I was hoping that you guys could point me in the direction of some memorable threads where these kinds of lessons can be learned the easy way. I haven't yet bought my RX-8, so everything from what years to avoid, what things to look for, how to shave the most weight, how to avoid burning seals, how much tire you can cram in the wheel wells (and if it makes the car any faster on a track), what shocks, spring rates, and sway bars do you prefer, how much toe and why (I did read the "post your camber settings" thread). Thank you in advance!

Genuinely,
Sam Harris

First welcome to the forum! second thing, I humbly am replying to your post because I am not an authority. All I know is what I've heard from club members who are seriously into racing on the track. I don't mind telling you who they are, because I have high respect for them, however - I will need to ask them first (courtesy).

The first thing I've heard from both of them:

Chassis:
Serious gains through stiffened suspension, large diameter sway bars, 4 point tower bar, and other tweaks to the chassis to make it more rigid. Also, the RX8 is blessed with large wheel wells, and you can probably fit up to 295 tires in front and back. The wheels and stiffened suspension make a whole dimension of change with this car. With light weight alloy wheels, you can have the best of both worlds. IMHO (This is humble opinion): The RX8 has greater aptitude for cornering gains, less aptitude over Horse Power gains. If you want a noticeably faster accelerating car, you're left with getting a good turbo/super. (I say this for other members on this thread)

Brakes:
Some how the RX8 takes to braking very well. With performance brakes (brembo brakes), you will probably notice shocking stopping power.

Draw backs:
This is second hand, and I don't want to steal anyone's thunder (because this is their remarks and not mine). The fuel pump and fuel lines have a quirk that is only noticeable when you are doing over 1g in the corners, it can be catastrophic if you are not prepared. What is it? This:

The rotary engine can use so much fuel, that during a 1g+ long left turn the fuel pump will run out of fuel because the fuel is being pulled away from the fuel lines (under the rear drivers seat) where it connects to the gas tank. This is more noticeable if you have a high powered performance fuel pump. From what I've heard, the way to fix this, is to have a second fuel pump (one you can switch off [motor burnout]) on the opposite side (right side) of the fuel tank, mounted under the rear passenger seat. (Basically you have a fuel pump under each rear seat). This made a difference for my good friend.

I encourage you to ask around about the items above, just to make sure I'm not full of it. I am only commenting from the experience of two other people, who independently have track experience.

I hope this helps out friend!
I've seen some pretty awesome RX8s on the track... there is so much hidden potential in these cars!!

Enjoy!

Gyro Bot, couple of things...

---with too big tires, you lose top end and acceleration. I've found 255mm a good compromise.

---just get some good pads and the brakes are fine even under racing conditions.

---the fuel cutout only occurs when you are 1/4 tank and below, regardless of lateral G force

sam_h if you are frustrated with the stupid forum search....just pull up Google and use a command in the search like this:

rx8club.com: Common problems with tracking

or

rx8club.com: Year to avoid

I wish ;)

sam,

i would send a pm to trackaddict..

he runs tt in nasa in the ga area..

beers :beer:

I've missed where else you get cut out. I got fuel cutout at nelson's ledges this weekend under 1/4 a tank coming out of the big sweeping rh carousel. Put my pedal down for the straight and nothing happened. But I've never heard of people having cutout on 'gentle' turns or straights. I thought I've seen most of those discussions but I know you've experienced most of the issues people have on the track.

For OP there aren't any real things to stay away from. Our chassis hasn't changed and there hasn't been any noticeable changes to the car until '09 and most of that is just bringing the stock version up to what good aftermarket parts get the 04's-08s. Avoid anything with a sunroof, but you probably would anyway, and base models w/o options tend to be the easiest routes. Your biggest concern with a used model is going to be the engine. Until the most recent flash in Nov '07 the engine management simply wasn't managing the engine wear well enough. People who maintained their cars were for the most part OK but most owners were probably putting entirely too much strain on the engine. If you can find a base 04, 05 that has had its engine replaced in the past year that might be your best bet. Make sure you get a compression check before buying anything that hasn't had an engine replacement if you plan on racing it.

The brakes on this car are fantastic. Put on a good set of track pads and you're good to go. Beyond that I'll defer to the guys on race teams but really the car was designed to be tracked from the bottom up. Too bad they ever built it with an autotragic.

+1

Fuel cutoff happens because we have a saddle tank that straddles the driveshaft so hard lefthand sweepers will slosh fuel to the right side and if it's long enough the fuel pump will starve. It's a combination of lateral load+time-fuel tank level=cough/misfire.

Gyro bot,

Thanks for all the ideas. In the TTD class I won't be able to make quite that many mods. Swaybars (2pts), Coilovers (5pts), and 255 V710s or Hoosiers (11pts) would only leave me 1 pt to spend (and a chassis brace with more than one connection point costs 2pts). Would it be worth running 245s (-1pt) to spend on a chassis brace? A rear lower chassis brace on a Cayman or Boxster adds about .4 sec a lap belive it or not, so you never know. Brake pads and good fluid are free, as are any wheels. Are the stock wheels light enough? I can pull anything out of the car I want so long as I cross the finish line above 3045lbs (with driver). There are no points for fuel pump alone if using OEM fuel and timing maps, sensor inputs and ignition timing.

Thank you and thank you!

Swoope, I instructed quite a few RX-8 guys at Road Atlanta back in 2004-2005. One of my students was there for his first track day and we went to Sonic for lunch. I hear through the grapevine that he's quite the time trial racer these days.




EDIT: I can't find any mention of fuel cells costing points in the 2008 TT rule book. Would that solve the fuel starvation problem?

Where and how has this occurred over 1/4 tank for you? I'm pulling 1.45Gs regularly on track and haven't found it a problem. Perhaps you have fuel pump failing?

Are you talking about sustained 1.45gs such as a long sweeper or high G's in quick chicanes? I've found it has a lot to do with time at high lateral loads. The longer the hard corner the more time there is for the pump to go without fuel and you see starvation. If it's just quick back and forth it doesn't seem to be a problem.

For example I saw fuel starvation on Pacific Raceway's turn #2 but not 3b. I believe mainly due to the sustained Gs on Turn 2 vs. 3b.

http://www.pacificraceways.com/road/roadcourse.cfm?

It's any sweepers - not just left or right. If either tank is low because the fuel has sloshed onto the other side you'll get the cutout.

They're relatively light (~23lbs) but for competitive racing they should be replaced.

There's a good thread on building two 8s for the Koni challenge series here:

https://www.rx8club.com/rx-8-racing-25/new-endurance-racer-build-137330/

There was a TV show linked on Youtube (I think) that had Speedsource letting someone in Japan drive in the Koni challenge. The drive started to get the fuel starvation issue and the Speedsource engineer told him that it's a common problem and the Koni drivers have learned that it is extremely important that they drive very smooth in any series of turns if they want to avoid the starvation so it doesn't sound like it's just the big swooping turns. It sounds like as the fuel level goes down it can occur on any turn if the driver isn't being extra-smooth.

I'll try to dig up the link.

Good info. I think we're in violent agreement on this. :)

There is a fuel starvation issue that needs to be addressed by either creating a new fuel cell (may be a requirement anyway) or setting up a new fuel pump.

Speedsource sells a new fuel tank (for track use only) that is suppose to take care of the problem. I don't know what mod they make to correct this. It is pricey.

Ah. Here we go.

http://videos.streetfire.net/video/B...-22_194195.htm

The race starts at 16:00 and he starts having fuel issues around 22:00. The Speedsource rep is talking around 24:30 about the fuel starvation issue. Just says they try to be very smooth in that car.

I'd say that on average I'm experiencing 1G or a bit more on sweepers I'm familar with. I try to ratchet up my speed to use the available grip I have (with a bit to spare for personal safety esp at higher speed) and that's typically where I'm at in those situations. Use the track map links below and follow along for some examples.


Mt Tremblant ...starting w/turns 1-2-3-4, going from ~100mph in a downhill right-hander at 1 that climbs perhaps 75ft to 2 at the top of the hill where you must be accelerating to avoid a nasty spinout over the top which drops off very quickly (fun!!) on the way down to 50-60mph at 4; then 5-7 a high speed run in the ~90-100 mph thru 6 decreasing to ~80 before starting into in 7. Turn 7 is one of the most dangerous places on the circuit as it's off-camber and you have to accelerate thru it pretty much full throttle or risk spinning.

http://www.lecircuit.com/circuitDocu...Eng1%20(2).pdf

http://www.lecircuit.com/circuitDocu...MT%20areal.jpg

Calabogie ... esp. 'The Ridge' continuing to 'The Spoon' and 'Left' Quoting, "The Spoon is a long concave turn to the right along which cars will carry maximum speed while constantly turning and dropping down to the apex.." This one is really fun as you are like in a long downward right hander but in a sluice where acceleration feels oh so right!

But also check the descriptions of other curves out there are plenty of high speed extended turns.

http://www.calabogiemotorsports.com/...23/41/lang,en/

It's very puzzling why you guys experience that and I (perhaps others?) don't under other than ~1/4 full tanks. I don't know why these conditions wouldn't give this starve-out, but I do know it only occurs with my car near or at 1/4 tank. Strange to say the least. Perhaps I'm just so smooth :lol2: I'd still suggest checking you fuel filter (OD had problems with sludge on his), or your pump pressure.

For what its worth I have a post going on regarding my first HPDE in my Mazda (not my first HPDE) and I mentioned that when I got below 1/4 tank my RX8 was cutting out about 3/4 the way down the long straights at Sebring.
https://www.rx8club.com/rx-8-racing-25/sebring-my-new-rx-8-a-158088/
It never happened in the sweepers just on the straights. At the time it seemed like fuel cutout to me but I was puzzled because I had a quarter tank on the gage. It never happened again after I got suspicious and kept the tank above half full.

It was doing it in long sustained left sweepers...like 5 sec over 1G. It did it with a brand new fuel pump NA...and with an upgraded higher flow pump with the turbo.

Did a bunch of mods...and haven't tested it yet...but it should be good now...2 pumps with the return going back into the cup to keep it full

HEHE, you figured out the secret that soo many of us race teams have been playing with for a little bit now. Believe me, it'll work well! ;)

It had better...or else I'm getting out the torch ;)

Just to pass along, we still get a bit of fuel starvation once we fall below 3 gallons. Figured out there is no way around it...always up for new ideas on the matter though.

Dry sump fuel tank? :dunno: collapsible bladder?:)

Good ideas, but we are limited by Grand-Am rules...dry sump=not stock, collapsible bladder=not stock...

Are there any RX8 race shops closer than 6 hours to me (DC metro)?

ROAR: Troutman, NC (379mi)
BERG: Rochester, NY (383mi)
SpeedSource: Sunrise, FL (1019mi)

Thanks,
Sam

Sam, I don't know of any other shops near you. Especially one with a Grand-Am ST program...that would help you out the most.

I just got off a 40 min call with an RX8 race shop (which will remain nameless) and his feeling is that if I buy an RX8 and just slap on suspension and tires, I'll be tearing up engines, trannies, and rear ends. He said I need a built engine, an '09 tranny, and a racing lsd, oil coolers, diff coolers, etc just to make the thing reliable.

I raced a 2002 Porsche Boxster S to a Mid Ohio lap record (for a boxster) and runner up National Champion in NASA's TTC class with less than $3k worth of mods. The car was bullet proof and gave me no problems whatsoever. I saw the price of RX-8s dropping and took one for a spin last week and really enjoyed the feel so I thought I could just slap on tires and a suspension and go race. Am I dreaming?

I would agree with the tranny. The car comes with a lsd, but it may not be the best type for racing. If you are buying the car used, the engine may be suspect. There have been cars that have had a string of engine problems. Get a compression check before the final purchase of the car. Oil coolers & the rear end shouldn't be a problem. You may want to drop the final ratio to 4.77.
Finances, for the moment, are keeping me from competing in TTD.

if you named the shop peps could could help you more with their known rep...:scratchhe why the secrecy? Beside that, sounds like a bit of a sales pitch. You can do susp/tires and have a go at it...if you break smthg, what have you lost...nothing..then spend $$ & get the mods as you''then know for sure what is unreliable with your type of use.

Since you have an OEM LSD and oil coolers the 'advice' already sounds a bit suspect...

Spin, there very few in the series that use a stock LSD...the move is to go with Cusco and 5.12 gears. Also, I have an idea of where he got his info and they def are not the leading RX8 team in the Koni.

'09 trannys still have their quirks we have been running them for a while now. The previous tranny had some issues but nothing that wasn't expected. As for oil coolers, stock is good but bigger is better in my experience...as for the diff coolers, have't had any issues with diff temps to even worry about.

ahhh soo :)

I'm not going to smear anyone's reputation on the internet. That's just not cool. He might have misunderstood my intentions or was just trying to look out for me without realizing what kind of racing I'm doing (not pro level w2w).

I8U, can you guys give me a call and have a similar conversation?

Thanks,
Sam

EDIT: 703-945-0232

I have a Grand Am spec Rx8 and would be glad to answer any questions that you have. I might also consider selling it. Shoot me a PM with your contact info and I will contact you.

Billy Bunn

Sure Sam, our team manager will be getting intouch with you. I'll give you a call myself as well.

[QUOTE=I8U;2702860] Also, I have an idea of where he got his info and they def are not the leading RX8 team in the Koni.QUOTE]

I love this comment. Thanks for putting it in perspective I8U.

Anyone care to address the heat issue for him (and their solutions) or is it only me battling 220 F on the track during the summer here in California. :uhh:

As for tires/wheels 255 40 18 are ideal for me. RPF1's are pretty popular here. I've seen guys with 275s and it seems excessive for the power we have IMO.

Also-I recently changed over to RP oil but I'm not convinced it beats Mobil 1. I'm interested in what others have to say about this...maybe it would be useful to you too Sam.

the only real rotary tuner (dont know if they are a real race shop) shop i know of in the d.c. area is pf supercars. they are located in manassas. but if you are only doing mods like coilovers and sways they should be waaay more than enough.

http://www.pfsupercars.com/

WOW Kersh, you recommend PF Supercars to the guy? What did he do to you? You may to do a little research on Peter Farrell, he had some issues with customers cars that landed him in court...kinda like what Mazsport is getting ready to go through now.


Senna, ahhh the infamous cooling issues. What can I say, we have done extensive work on our cars to drop the cooling temps. We run Ron Davis custom radiators, and have done a little work to the water pump, can't get into specifics about that though, and ofcourse you have to lose the antifreeze and run straight water and water wetter. Our track temps hover around 180-200 depending on track conditions.

So,

-difficulty cooling
-fuel starvation
-burnt seals
-weak transmissions
-less than advertised hp (which means it may not be fairly classed in NASA due to rated pwr/wt ratio)
-way less than normal torque (less area under the curve)

You guys are not painting a very pretty picture for the RX8 as a race car. :scratchhe

Sam, you've been around awhile...racing isn't real pretty in general. lol

The RX-8 has it's quirks but it is a good race car once it's dialed in.

Advertised HP is 232..., which you can bring to 250 with a Cobb AccessPORT.

Search for posts by TrackAddict. He set a few track records in TTD down in the SE with his RX-8. As I recall, that car was equipped with Racing Beat suspension + Koni Yellows. Can't remember the type of tires off the top of my head...

Like every other car this one has it's limitations. You did ask what to worry about when looking for one - not for reasons why you should buy one. ;)

Besides you've already been in one around the track so we don't need to give you a pitch about how its a lot better on the road then on paper. You already know that.

Sam,

I haven't read over the rules for TT in a while, but I feel that to be competitive to TTD really all you would need would be everything you pointed out earlier. It also would be beneficial for you to go to a 17" wheel if you can, and then run some of the wider tires. I wouldn't go over a 265 though. If that gives you enough points back to do the brace, definitely do it. As for tires, we only have experience with Hoosier's (Koni Challenge compound and R6's), so I can't comment on how other tires like the Toyos feel on the car.

Brakes on the car are fantastic in stock form. Really all you need is some track pads. We recommend Cobalt XR2 compound in the front and XR5 compound in the rear. The pads have a more manageable initial bite than other pads but still hit hard enough to pop your eyeballs out. They have also proven to be very easy on rotors. If you wish to upgrade your rotors, we have had much success running Racing Brake two piece slotted rotors. Reducing the rotating mass does wonders for the car.

Considering it's TT probably the longest you will ever run will be 30 minutes, maybe a 40 minute session once in a blue moon. The Diff / Trans coolers are unnecessary for those short stints. Upgrade the fluids (75w90 gear oil for the diff, and it appears that a 75w90 gear oil mixed with ATL works the best in the trans). '08 Transmissions are fairly fragile, but as long as you take your time shifting and don't cram the gears it should be ok. However, buying used, it is impossible to tell how the previous owner(s) treated it.

An upgraded radiator and water pump would be highly beneficial. And of course like I8U said, run straight water with a bottle or two of Water Wetter.

As for oil, we have done plenty of testing on virgin oils, and as it turns out the Red Line brand has the most anti-wear additives and has been a very good oil for us. We run the 50wt race oil.


As for other optional mods - I don't believe it would be necessary to get a built motor until your first one fails. And even then all that is really necessary is ceramic apex seals. Porting / Polishing won't be worth the points incurred. Axial Flow Engineering short shifters are fantastic if you stick with the '08 trans. They are working on getting one ready for the '09 style transmissions. The Cobb Accessport with tunes made by MazdaManiac have shown tremendous hp gains.

Adding the auxiliary fuel pump inside the tank is a fantastic mod as long as it is done right. If it doesn't give you any points I would definitely consider it. Without it, keep the tank topped off and you should be fine.

Well - that's what I can think of right now. I can tell you that you will not regret buying the RX-8. If you think of anything else or if I missed something let me know. Feel free to PM me if you would like.

We will be at Road Atlanta for the final NASA-SE event on Decemeber 5, 6, and 7th, so if you are around be sure to stop by!



Adam

Mazmart makes an upgraded water pump and Charles R Hill makes an upgraded radiator that should solve #1.

My humble advice on burnt seals is to pre-mix with idemitsu rotary premix. That's what most of us on engine #2 have been doing. There's a pretty big thread on this as well. Also you'll see some vacuum increase with adding premix.

Ahhh yes, I totally forgot about premixing. One ounce per gallon of fuel in a race setting.

Thanks Adam, I knew you would have some great insight on the matter. Looking forward to Road Atlanta. ;)

In what world?! Yeah 232 adevrtised, meaning 180ish to the wheels in a stock MT...add the AccessPort, and 200ish is possible.

Quite honestly, I'm a little surprised that you're seriously considering the Rx8 in light of your past experience with other higher hp'd cars. As much as I love tracking this car I have no doubt that it's not going to be sufficiently powered for me in the not too distant future. I'm already dreaming about a 3 rotor option and I suspect NASA can find a class for it to run in.

As it is-I run in HPDE 3 and my times are upper middle pack on stock suspension (outside of sways) amongst a bunch of higher powered stuff. But I'm lower on the learning curve in terms of getting everything out of a momentum car-compared to you. It's a challenge for me now, would it be for you?

Despite conventional wisdom, faster does not necessarily mean better. You go out on the track and drive faster than you ever have in your entire life and it feels awesome. So then you think, if X is good, then Y will be even better!!! Once the newness of speed wears off, the thrill isn't quite the same and you have to go faster and faster to replicate that same feeling. Powerful cars drive much differently than momentum cars. People who like one tend not to like the other, but both present their own unique challenges. However, there are two other ways to capture the thrill if it ever fades. First is to concentrate on all the possibilities. Try to nail your braking points to within inches lap after lap after lap after lap. Then, once you have a line perfected, completely mix it up. Take a corner on the inside, the outside, etc. Try lifting throttle mid corner and catching 45* slip angle and recover it. Try pretending that you're going into a turn and the brakes all of a sudden don't work. Imagine cresting a blind hill and seeing antifreeze on the apex and being forced to adjust your line mid turn. This not only makes it interesting, but it makes you a more experienced driver...a safer driver... and it prepares you for the ultimate thrill--> racing. There is no comparison really between trackdays and racing. Once you strap that transponder in your car (and especially once you slap the cage on it and start running door to door with your friends) the adrenaline levels exceed that of an 8G bank in an F-18 (believe me because I've done both). For me, the move from track days to w2w is 10x more exciting than the move from a Corrolla to a 911 Cup car!



Adam,

I used to work on cars myself but these days I do 80+hr weeks and live in the city where I have no garage and no tools. So, I would be very excited about having a shop handle the purchase and build. I like what you have to say. I'd love to come to RA--it's one of my favorite tracks--and one of my long time racing buddies is seriously considering renting one of your cars for that event. But I live a good 9.5 hrs away now, so it's unlikely I'll be able to make it. Why don't you give me a call and we can talk about a build. 703-945-0232



What may kill this idea in the end is closeness of shops. Given that I have no garage or tools these days, being close to a shop that knows what the heck they're doing might be a deciding factor. There are literally three BMW race shops within 2mi of my apartment.

Swoope, I instructed quite a few RX-8 guys at Road Atlanta back in 2004-2005. One of my students was there for his first track day and we went to Sonic for lunch. I hear through the grapevine that he's quite the time trial racer these days.




[/QUOTE]

wow,

small world! if we are both talking about nabil, you should really talk to him..

btw, he has over 90k miles on his car, and 7k are track miles. i am pretty sure that is accurate.. it was talked about last track day..

running the car hard is good!

beers :beer:

Thanks for your insights. I'll definitely keep your ideas/practices in mind as I move along the learning curve. I may have given the wrong impression though. For me track days are a means to developing my ability to run w2w in a racing series, not an end in itself. The track day vs race day comparison is a no brainer.

Admittedly though, and it might just be me (right now) but the idea of piloting an F1 car or the Puegoet 908 against equal competition strikes me as being more fun than piloting a spec Miata against equal competition.

Keep the car cool!!! -Oil and Water.

Ron Davis Radiator (spec'd from ROAR Racing - probably the best one available that fits in the factory location).

Upgrade the oil cooler with larger more efficient units (not as important as radiator, but VERY important none-the-less).


Aah yes, a very well spec'd/sized radiator ;)