We have to work within the allowances of the class rules. Trying to do everything I can in that regard, but there are some conflicts between min weight and things like heat/airflow management (fan shroud vs just a small fan on the radiator shroudless), reliability (lighter S1 glass-box vs stout but heavier S2 trans), etc. The very first post of this thread discusses the allowances which there are many factory parts we either can't modify/change or they're hard to modify/replace without also making them heavier.

That said, lighter may not be better. It's a game of trying to figure out when the change will make the car faster regardless, like larger/heavier wheels & tires. When it's said and done, pulling weight from the front if an RX8 is much harder. Some of the bigger things were already allowed in the previous class like front brakes, exhaust system etc. So the biggest front weight reduction items now are clutch/flyweel, AC removal, emissions removal (air pump system, etc),radiator/fan/shroud system, engine oil/cooler system, etc.

But to give some more examples, we're allowed to change radiator but the replacement has to maintain the minimum width/height/thickness core dimensions as OE and attach at the same mounting points as OE. The only way to have a crossflow 2-pass radiator is to shorten the core width to fit the end tanks within the width of the frame rails/undershroud sides. So thats out. Then you're looking at just the conventional top/bottom end tank radiator just like OE. I never had cooling issues for what we do. Since the OE radiator is both dead light and adequate then IMO it doesn't make sense to change it.

We're allowed to modify the engine oil system externals so if you start looking at the oil cooler system the first thing you see is Mazda already made all the lines dead light. I'm not feeling like just one cooler in the OE front bumoer corner position is adequate. Not allowed to cut the OE shrouds/front bumper, so where can you put a large enough single cooler and vent it? It would have to be in front of the radiator. Scratch that. Unless you can find an oil cooler that's lighter than OE and also either as or more efficent than OE then IMO it doesn't make sense to change much there either.

and so on ....


Edit: oh wait, that was a joke about the missing engine trans, lol ...



.

Another wheel question

The ebay hub (yeah hush I know...) wouldn't fit with the clock spring still on. So we removed the clock spring, as seen in the pics attached I'm unsure if I can plug the resistor into this guy or do I need to plug the resistor into the airbag harness that comes off the clock spring?


She doesn't like how far out it comes, so we'll be getting a new hub and ngr slim quick release anyway. Hopefully the new hub will work with the clock spring still on (plugged in)

Thanks in advance for the help!!

Make sure you figure out how to do the steering angle sensor properly...otherwise you won't have TC and more dash lights

Only if you have the TC option I believe ....

True ;)

we reset the ecu and did the 21 brake thing when done.
only light on is airbag..

we do have trac control. idk about any sensor but the car seems to be working properly. at first it would start up, rev around 1400 for a sec, drop to 500 ish, then catch itself and hold at 900 ish

she hasnt complained so im assuming its working well. just too close to her she said, so a shorter hub adaptor will be ordered and possilbly a slim QR if the shorter hub still makes it come too far out

sorry, pretty sure that the yellow connectors are used for the airbag circuit

ty !

FYI, back in Post#1 I had the 2009+ triangulated front strut bar listed as an applicable update/allowance. However update/backdate requires the part to bolt in and attach without modification to any attachment points. The rear bolt-in point for the 2009 tfiangulated strut bar is an additional bracket that attaches to the upper firewall/cowl. The problem is that to install this bracket on an S1 requires drilling the firewall/cowl to mount it. This isn't allowed, so in turn IMO the S2 3-point strut bar or equivalent replacement can't be used on an S1 chassis .... so I deleted it from the list at the beginning of the thread.



.

Fellas, I have a curiosity, I'm not in DSP this season but am thinking about it, I was looking at spring rates and reading Autocross to Win online and was focused among other things on this natural frequency thing and wanted to see what you guys thought about it or had heard.

Basically he says that for cars without Aero on slicks you want natural frequencies of 2.2F/2.5R there or thereabouts, which on the RX8 would be about 10k/11k assuming the car weighs 2900 and a fat driver like me is 270.

According to what Ive seen some guys run in street prepared and such that seems like a soft wheel rate, but when you consider that when those rates are coupled with the sway bars, you're looking at a roll stiffness of over 7000#ft/degree. Now Randy Pobst recently said that generally speaking your car will lean 1-3 degrees under max cornering with 1 degree being too stiff and 3 sacrificing some responsiveness, but with that 7000#ft/deg roll stiffness you'd need to corner at over 3 g's just to get the 2 degrees of lean!

They say a suspension has to work to work, and if everything is too stiff then its akin to using a solid chassis and relying on your tires to do alot of the shock absorption, which is good I guess if its cold and you need to work them but it seems like youre best off being a little softer.

I dunno I'm rambling at this point, I'm not trying to upset any conventional wisdom on spring rates but I'd love to be regaled with tales of what sort of trials and tribulations moved to establish the conventional wisdom. Hopefully something more than Mr XYZ did it and he's fast so we do it too, although that would be refreshingly honest to hear if it's the case.

What are you using to determine your numbers? I know for a fact that the previous public versions on the FatCat site don't output accurate information.

Nathan, you're overthinking it. No amateur racer has enough tire data (not to mention stiffness & compliance data for the vehicle) to arrive at "ideal" spring rates using math. The natural frequencies (and the roll angle thing) are a rule of thumb that take the specifics of the vehicle out of the equation. It'll get you 75% of the way there, but cars--and especially production cars--are weird and you'll still have to tune to get it right.

Do you want to arrive at a particular roll rate using more bar or more spring? Do you understand why you'd pick one over the other? How does it affect what your shocks are doing in roll versus in pitching or ride motions?

For that matter, how did you arrive at your roll angle numbers? They change depending on where your roll center is, and the geometric roll center isn't actually where the car rolls around either. And how do you know that a certain amount of suspension travel is good? Compliances are going to play a much bigger part than you might think, and they could swamp out any well-intentioned calculations that you try to tune with.

I guess what I'm trying to say is that this stuff is complicated. For almost everyone, the answer is to start somewhere that is proven to be close and then take a lot of time to tune and tune and tune. Even the automotive OEM's with all of their engineers and simulation power rely on a few well-calibrated butts to dial in their vehicles' chassis characteristics. I think the story that you're looking for is that a lot of people tested and tuned to make their cars fast with certain tires, and a statistical analysis showed that they ended up within a certain range. It's unfortunately not very glamorous or straightforward.

in DSP the aero will impact it as well, the rear spoiler more so since the rule allowances favor it's handling impact more on an RX8 than the front splitter. In short, you will need a higher rear rate to compensate for a big rear spoiler. In fact, you probably won't want to make it as big as the rule allowance permits.

Hmmm, DSP is a big can of worms :-P

I was using the public Fat Cat site to get the roll stiffness number so that's in question, I also had my fat-ass progress bar numbers in there which really raises that number alot.

also I was assuming I had a cg height of 17 inches (~18.5 stock, and I was lowered about 1.5" in STX trim) to get the roll angle as a function of lateral g.

The Nat freq. and roll angle thing like you had said was just rules of thumb yes, but I guess I was thinking if I came into DSP and there's not alot of shared data those rules of thumb could get me close.

I hadn't thought much about aero (probably cause I went to a Baja SAE school and not an FSAE school heheh) but I'll have to read up on that some more.

Man, there is so much tuning I would do if I had gobs of data acquisition stuff, I dont trust my butt entirely yet, maybe you guys are more sensitive than me haha

Here's a tire question for an R-comp newb, do you think a set of 275/35/17 A6's would last a whole season (10-15 events) with a codriver? I can find lots of widespread testimony on this but not so much that is RX8 specific.

Also any thoughts on the A7? it's supposed to last a little longer and drop off more gradually

Thanks fellas

Oh one more thing, I'm looking to source 17x10 +45..50 wheels for this, if anyone has an extra set they could part with, I'd be happy to purchase them. Additionally I'd like to offer an opportunity to buy them back at the end of the season in case you cant bring yourself to part with them permanantly, so I can sort of rent them so to speak just in case DSP isnt for me, just a thought.

Not the lightest, but cheap

ROTA Wheel RT5-R2 17x10 (5x114.3+50mm, 73 Hub, Hyper Black)|Rota Racing Wheel

ps: those who can't search, always are dependent on someone else ... :)

I looked up the Rota after I read you had mentioned you could buy three sets for the price of your modular wheels :-) I thought that was the wheel to get for my budget build! Rota seems to carry a very negative reputation from what I read though, i thought Id ask if anyone had a used set to sell for a similar price but higher quality.

Ive committed to CS for the season on encouragement from my buddy Danny who seems to think I could walk that class locally, but DSP seems alot more fun. I suppose as this season goes by I'll do as much learning as I can and try to come out swinging for 2016. Hopefully I'll have the knowledge the budget and the execution to not be totally embarrassing!

I'll be watching here to see how you guys develop and for videos and stuff

I wouldn't have any hesitation using those Rota wheels.

You always have the lighter Enkei RPF1 option, but +38 is the closest you'll get for offset

I was looking into cost of materials and workmanship to copycat the BHR long tube header and determined that their asking price is actually pretty damn reasonable. Any of you guys going with it? I'm curious what kind of results you see...

Building my own short tube to replace my worn out header that was built in 2006. Otherwise my thoughts on it are elsewhere on the forum.

If you already have a Racing Beat header and 3" midpipe then cutting the collector/OE flange off, fitting a 12* 3-way 1.75" x 3" race collector from Burns etc on it and then mate it to your 3" midpipe will get you very close. No additional tube length is necessary, but you can do that too if you believe in the tooth fairy ...

slip joints and clamps are cheaper and lighter than flanges too.



.

Well I had a set of Rota Slipstream 15x8's for my old FC and had them fail on me due to a blatant design flaw, so for me, never again. Maybe those 17x10's will be ok, but I won't give them any more of my money after they sold me garbage that could have lead to an accident with all the associated health and financial risk.

If you can wait, 949 Racing is bringing back their 17x10's, supposedly this spring, but they have a history of pushing back release dates. The other option is Forgeline F14's, which come in a 17x10 with custom offsets for $335 each. Each option is apparently under 18lbs. There's also the used 17x10 6ULR option, if you can find any for sale.

ROTA supplies OE wheels for many manufacturers, the supposedly bad reputation is mostly intrawebz clowns parroting BS they know nothing about. Not to say they haven't had any failures. Rather, I have seen failures and bending in many wheel brands that nobody gets the least bit fracked out about.

Also a while back they released a notice about some copycat manufacturer in China selling fake ROTA wheels with the ROTA logos, markings, etc on them, so sometimes a bad wheel may not even have been made by them

What happened with mine, as far as I can tell, is that they took a wheel designed for a 4 bolt pattern and drilled it for a 5 bolt pattern for a small run of a special size (15x8, 40mm offset, 5x114.3). This meant that there were pockets in the back side of the hub (where they stamp or cast information) that had sharp corners within a couple mm of two lug holes in each wheel. Upon checking lug nut torque between sessions, I noticed one wouldn't tighten, so I investigated further and found a crack from one of those pockets through the lug hole. I took them all off at that point and swore off Rota.

I bought them back in 2007 from what I thought was a reputable vendor, so I'm pretty sure they're real Rotas, but it was a bit of an unusual situation. BUT they should NEVER have allowed those wheels off the drawing board, never mind out of the factory with such a design flaw. That's what really made me upset with them.

I wasn't referring to your situation and don't doubt your story. Sometimes sh-t happens with any manufacturer ...

So I was just getting ready to put my engine back in and the friend I borrowed the engine hoist from needed it back due to a dropped valve on his car. So it will be another week or so for that, but I still have a ways to go regardless. Some things going on ...

Bought a Miata steering shaft adapter and quick disconnect from MiataCage.com. It requires some machining to work with the RX8 steering shaft sensor (not required in s true race application that deletes the sensor/turn signal assy), but is worth it for the low cost.

Installed the Racing Beat primary fuel injector Renesis dummy plug kit since those injectors and rail aren't going to be needed. Working through the rest of the engine bay fuel supply setup now.

Putting an S2 fuel pump in the RH saddle as the engine supply pump and extending the OE wiring to power it using the OE low/high speed strategy. The S1 pump wi be wired and plumbed separately to supply fuel from the LH saddle directly into the S2 fuel pump cup on the RH side. My goal is to wire it with a relay and a trigger tied to the LH level switch so that it turns on/off based on fuel level detection. Also a manual forced-on switch to transfer fuel to the RH saddle after dumping a 5 Gal fuel refill jug. The siphon strategy is completely eliminated as well.

Eliminated the OE oil fill and vacuum tank assembly from under the UIM. Decided to hold off on some more radical UIM mods until after I get the everything up and running ok first.

Having custom arms made for the front speedway bar setup I need with the deep offset/wide wheels I have. Can't get the new S2 rear arms installed until the engine is in, after which I can then move the car out of the back corner where it'll be easier to get to. Also bought a 4.77 S2 diff, but can't get my S1 diff out for the same reason and drop the OSGiken LSD for a refresh before slapping it in.

Laying out the radiator shroud & fan assembly this weekend along with the header pipe routing.

Don't really expect to have the car in competition until maybe late June/early July fue to being out of the country for 4 weeks ...

Installed the Racing Beat primary fuel injector Renesis dummy plug kit since those injectors and rail aren't going to be needed.

Oh Nice, are you going with the Formula Mazda style intake manifold then and a couple injector throttle bodies?

That should get you 20+ hp based on the old rotaries/manifolds and what I have seen of Renesis Formula Mazda power charts.

Glad someone is going to take the fight to the BMWs with some HP. RX-8 chassis far outclasses the BMWs, just let down in power.

Having custom arms made for the front speedway bar setup I need with the deep offset/wide wheels I have.

Aww, bummer its not as easy as the FD where you can put in a shorter torsion tube.

The Pro Formula Mazda Renesis engines use the UIM with the same underpart removed, but only a single throttle body like OE. It's cable controlled rather than electronic with a MoTeC ecu. I still intend to use the Adaptronic because it needs the factory TB to work with the OE OMP.

I've been running my own custom speedway bar for years, but it has an interference issue with the wide high offset wheels. So I am going to a shorter tube, but this time chose to have someone else make the necessary arms to my specs to take some of the custom load off myself. It will use roller bearings rather than brass or urethane bushings. Also may run a rear speedway bar too.

Didn't make as much progress this past weekend as expected. In the short term I decided to order the RB header and modify it initially and pursue the custom header longer term. The custom header will incorporate a custom engine mount bracket already being fabricated this week which opens up the pipe routing possibilities quite a bit.

For future reference the S1 OE radiator core dimensions I measured are 25.50" wide x 14.13" high x 1.00" thick. Any aftermarket radiator must meet or exceed these dimensions to be SP legal (total weight too). The core can't be smaller in any dimension or the radiator itself can't weigh less. Still trying to confirm S2 radiator dimensions, which is an allowable UD/BD part. If anything it is bigger rather than smaller so likely not relevant.



.

Sounds like you are building a real monster, Team. Good luck with the rest of the build. Will be fun to see you, Monnar, and Kuhn at Nats in Sept. :beer05:

Welp, I have no business in this
class given that this is my first autocross, but I'm running in DSP this weekend here in the Kansas City region. Mainly because when I bought my car, it had 9.5" wheels on it and I can't justify the cost of new wheels right now.

But honestly, I don't expect to be competetive in any class. I'm primarily looking for a place when I can drive my car at its limits safely and legally.

It'll be like playing a video game on "hard" mode, right? :)

I just dropped about $500 for fuel/oil hose and fittings today :squint:

I figure 9krpm must have at least several thousands dollars invested in his :uhh:

1-1/2 years of d1cking around later ... yaaaaay


https://cimg0.ibsrv.net/gimg/www.rx8...6cba25f126.jpg


https://cimg1.ibsrv.net/gimg/www.rx8...3114b00094.jpg


https://cimg2.ibsrv.net/gimg/www.rx8...8933bc827c.jpg


https://cimg3.ibsrv.net/gimg/www.rx8...32f4c2113a.jpg

So I ran my first event this past Sunday. I was the only one runing in DSP but I ended up about 5 seconds slower on all-season Potenzas than the fastest STX guys on sticky tires. They were posting times in the 49s and my fastest run was a 54.6.

Watcing the video and given that my last run was a 1.5 second improvement, I'm sure the car has much more to give the way it is currently set up.

http://youtu.be/KxW8xzaqgh0

Any feedback is appreciated.

Now that is a crankcase vent.

It's just a flanged tube with a vent filter on the end :dunno:

Here are some shots from this weekend.

https://cimg0.ibsrv.net/gimg/www.rx8...76c67cf2f2.jpg


https://cimg9.ibsrv.net/gimg/www.rx8...aab63de115.jpg

Lots more of the other cars here:
http://pattersonprints.smugmug.com/Motorsports/Kansas-City-Region-SCCA/2015-KCRSCCA-Solo-Event-1/

Team do you know anyone that needs a Quartermaster 5.5" Twin Disk?

Bryan if that was your first event ever Id say you're building off a pretty good foundation. If you dont plan to do any National events where youd get protested than you in all likelihood could just ask your local competitors to just let you run in STX until you get the wheels updated, no one minds until youre beating them all the time.

A really great driver on all seasons will finish strong midpack against guys on proper tires, they're really only about 2 seconds per minute slower, and thats with the new crop of extreme tires out there. So think of every run as an opportunity for driver improvement and try not to get frustrated theres till time to be found out there.

you could pick up stock sized wheels or 17x8 for pretty cheap and run in CS with minimal prep, that'd be a good place to start. DSP gets really fast and staggeringly expensive. I wouldnt recommend pursuing it yet

Thanks for the feedback, Nathan.

It's good to know about the roughly 2 seconds per minute because that gives me a realistic target to hit before I really need to consider upgrading my current 400 tread-wear tires. At this point, I know that I'm the slowest part of my current set up :)

I'm going to keep an eye out for a good set of used wheels but in the meantime, I'm going to keep running and comparing my times to the STX guys as that's really more in line with my car's setup.

As far as my actual current class - I'm not expecting to be competitive anywhere in my first season, so It doesn't matter to me, really. We're not on-track at the same time :)

Thanks again!
Bryan

finally, out of the back corner from 1.5 years ago and now with some elbow room the real work can begin ...


https://cimg5.ibsrv.net/gimg/www.rx8...1b9f8ebbbc.jpg



I love the smell of gear oil in the morning :) and no sleep before starting work :rolleyes: OSGiken LSD shipping out for a refresh then getting slapped into a fully rebuilt 4.77 S2 diff ...


https://cimg8.ibsrv.net/gimg/www.rx8...269c0797ff.jpg

S1 4.44 diff out



https://cimg0.ibsrv.net/gimg/www.rx8...06ea6f0bf2.jpg


OS Giken LSD out and off for a refresh ...


.

Looks good Team.

I'm making the jump from STX to DSP this year. Should have been in DSP last year seeing as when i bought the car i was catless, but other than exhaust and BHR coils there was nothing else done to it. I Picked up the JoeFis aero kit earlier this month and just got the spoiler on last night. Splitter will hopefully be happening sometime this week. Hawk HP Plus brake pads are here now. Still debating whether or not i want to "upgrade" the rotors to Hawk SP performance slotted ones. Seeing as i keep hearing that our stock rotors are pretty legit.

I can only determine one meaningful physical change between my original 2005 S1 rear suspension arms and the later S2 rear suspension arms. The rear tie-rod center tubes are approx. 0.070" larger OD and the resulting weight difference is obvious just holding them both in your hands. I recall the road racers complaining that the S1 tie-rods would bend too easily in minor wheel-wheel contact. So it was likely done to address this. Otherwise all the bushings, ball joint ends, lengths etc. are all identical to a tee :dunno:

Another forum myth up in smoke ... :squint:

What about the chassis pick-ups? Could the toe-control link mounts on the chassis side be moved to change the toe-curve in the rear?

Without changing the arm lengths it seems unlikely. I considered an S2 subframe, but was kind of leary about buying one from a salvage yard due to concerns over whether it would be tweaked or not in some way. In my mind any geometry changes might correspond to revising the rear uprights. There is something different about the rear shock perch and rear spring positioning on the S2.




.

f'd off for over a year and now it's payback time burning the midnight oil :icon_no2:

Wasn't sure I'd remember how to put the dash back together after tearing it apart 18 months ago, but it seemed to go well. So the radio and stereo components were all removed then, but I decided to keep the radio/dash cover plate for simplicity. If I need another 1/2 lb. weight reduction :lol2: I'll make a custom cover, but the HVAC dial controls will have to be fitted to it since nothing in the SP rules says we can remove those parts.

Otherwise I finally got the race steering wheel setup installed. Was impressed with how rigid the ultra-lightweight drag race aluminum steering wheel was when I first received it. However, after mounting it up not sure if it will cut it or not. It''s fine for turning, but is not suited for any pushing/pulling motion forces. Might have to rethink that one. Essentially the wheel is now positioned back about 4" more rearward than the OE wheel. So no more cramming my knees into the dash to get close & personal with the steering wheel .... yaaaaay

Otherwise the components in the following pics are:

1. MiataCage.com splined & tapered Miata steel shaft adapter. Has to be machined/cut off to work with the spring-loaded extension from the front of the turn signal/wiper assembly. I have a non-DSC base model so no steering sensor. Might be an issue for those that do have DSC unless you disable it by pulling fuses etc.

2. Aluminum cover-plate to cosmetically fill the hole in the steering column cover face. Bouhgt it from McMaster-Carr and modified it to fit/bolt on. Super thin aluminum, weighs nothing, painted it flat black to match.

3. 2" aluminum 3-hole extension from Joe's Racing.

4. MiataCage.com quick release assembly.

5. MiataCage.com 3 hole x Grant 5 hole aluminum adapter.

6. RJ Max 13", 1 lb aluminum steering wheel

7. Hardware fasteners from Fastenal to make it all bolt together

8. Aluminum mounting bracket for AiM Pista display/dataloger riveted to top of steering column cover. This is sold by Mazda Motorsports for the Miata. Tweaked it some and it fits fine,


https://cimg1.ibsrv.net/gimg/www.rx8...0cb6876094.jpg

Steering wheel with quik-disconnect removed


https://cimg5.ibsrv.net/gimg/www.rx8...d186d6e2e0.jpg

SIde view, fully installed


https://cimg7.ibsrv.net/gimg/www.rx8...28cbb3ffde.jpg

Front view fully installed



Also some detail work to re-mount a few items resulting from allowed component removal, in this case specifically the air pump. So tidied up the wiring, found a new place to position the baro sensor, and also a custom bracket for the fuel pump low-speed/load resistor assembly.


https://cimg4.ibsrv.net/gimg/www.rx8...67b8247b8b.jpg

new home for the baro sensor,


https://cimg5.ibsrv.net/gimg/www.rx8...46cb8305dd.jpg

aluminum bracket for the fuel pump resistor


need to get some sleep now ...


.

Overhauled the 4.77 diff as a precaution. $180 for all new bearings, seals, and pinion crush sleeve from Mazda Motorsports. The local drivetrain shop charged $285 to tear down the original S2 diff, install the new parts along with the OS Giken LSD, painted the housing, bead blasted the rear cover, bead blasted the diff mount, and pressed in the RX8 Performance delrin bushings (already had urethane JDM bushings from STX previously).


https://cimg8.ibsrv.net/gimg/www.rx8...f86f108a03.jpg

Fully rebuilt S2 4.77 diff with OS Giken LSD and delrin bushings



I did get the thicker OE S2 radiator test fitted. Bolts right on like factory using the S1 hardware. Seems like you could re-use the OE fan shroud on it, but I did not confirm actual fitment since it's not my intention to use it.

Any way, off to Japan until the end of the month so everything will just sit. Things left to finish:

1. Work out front speedway sway-bar details
2. Rework fuel system; 2nd pump, wiring, all new flexible fuel lines
3. Rework/reroute oil cooler lines that cross engine bay - flex-hose with AN fittings
4. Fabricate new radiator fan/shroud assembly. Can likely use OE fan setup short term if necessary
5. Finish UIM/intake system.

Incredible attention to detail Team, your build seems much more thorough than anything I could cobble together with my time and budget :-)

I hoping to just make it happen with revalved Bilsteins, stiffer springs, 17x10's, a 4.777 and a good seat. :-) I feel like those are the big ones to hit and if nothing else the car will be fun to drive, I'm already removing and installing my wheels and tires(RivalS) in CS, so I figure I might as well be bolting on something stickier fi i have to go through the trouble.

So I guess I wont intimidate anyone with my half-assed build but at least the car will be fun to drive until I eventually get tired of being crushed by John Vitamvas locally.

Still in Japan almost another week before I can get back on it. Itching to get going on it now, but some of the upcoming work will be a little difficult. I'm taking time to clean things up, anti-seize on all threads, etc. as I go, so this drags things out some.

Looking good Team, can't wait to see it out this year! (Assuming I make it out there myself considering I need to spend all my money to rebuild the engine... ugh).

For anyone interested since this is the DSP thread, here is an article I wrote that got published onto Mazda's website. Might be helpful, might not. MAZDASPEED Motorsports Development

(God I haven't posted on RX-8 club in forever...)

Good article...thanks :)

So I'm trying to put delrin bushings in my front UCAs, and I noticed that my UCAs don't look like they'll actually accept them if I press out the OEM bushings. Do I have weird arms? The rear bushing carrier isn't a full cylinder, so the steel bushing can sticks out into open air as shown (I already removed the inner metal).

https://cimg5.ibsrv.net/gimg/www.rx8...4e3aa1eb96.jpg


Looking around online, I can't see other arms that look like this. They all look like this:

https://cimg7.ibsrv.net/gimg/www.rx8...7d3bd55f6f.jpg

Was there a change made at some point? I think I'm probably just going to try to get all the rubber out of that can and make bushings that press directly into it, so I'd like to know if that's a terrible idea for any reason.

Wow, never seen that before. Are those the original UCAs?

What year is your car? If it is early model, there was a TSB regarding cracking control arms and parts were updated. I took mine in to have them checked but there were no cracks at that time, so nothing was done. Later one broke at the track and put me into a wall.