SCCA STX E30 Build/Introduction

[DblTrbl]

Race2win --- Thanks for sharing. Although for the time being, I'm into autcross just for fun, I want to let you know that I've enjoyed and learned a great deal from this thread. Good luck in our endeavors. I'm sure you'll keep us posted.

Carl

[imprttuner88]

I should probably not dump a shit ton of money into it and just buy an rx8.

It's what I did :p

<------ '05 model myself

[GreyLens]

Craig Wilcox had a short stint in a Cooper back in '06 in STX. It couldn't hang with the WRX (at that time) so he aborted it. (one example is Walnut Ridge NT in '06)

I'd love to see some more diverse cars in STX. a JCW Mini and Mazdaspeed 3 would be nice to see developed for the class.

It looks like I'll be running against a very nice 2008 WRX with an experienced driver. He used to run in STU. The STU class here in SA/Austin is a fast bunch of national level types and he always did reasonably well in a tough field. We also have a 2008 Mazdaspeed 3 that just moved to STX this year. I looks like there will also be another MINI signing up in a month or two when they move to Austin.

Last year I battled a 1989 Civic (formally two time national champ car with a relatively new but very talented driver) because of the class hopping thing going on then. I was finalizing the suspension and other things throughout the year so I barely beat him a few times. But, now I think I can take him regularly. He's moved to STS, I guess, but I'll still watch how we compare.

This will be a tough year as well judging on the past performance of the WRX in STU last year. I've watched him drive...very smooth and aggressive. Should be great fun.

I'll post brief results here just to let you know how it goes.

The technical discussion here is very helpful. Thanks to all the contributors.

[BlackbirdM3]

I installed the rear TC-Klein Koni sports with the mono-ball upper mounts and holy cow, its a different car. I started with the shocks set full hard and its fantastic. I can't wait to get the front struts on with the adjustable camber/caster plates and Treehouse control arm bushings. I think these springs might work, I don't know that super hard spring rates are the way to go. I might be wrong, but with just the rear shocks swapped out, its impressive.

I can get the back end to start to rotate now. I haven't had a chance to really push it through a hard tight corner, but it feels like it might try and step out now.

Will

[BlackbirdM3]

Speaking of testing dates ect, about twice a year a friend and I organize and put on an autoX test and tune day at Sears Point. We piggy-back onto a Trackmasters track day and use the whole paddock. I'll keep you guys informed for when we do another. There is so much driving time that people usually call it quits well before the end of the day. The usual complaint we get is "Too much driving time"

Will

[GotCone?]

Craig Wilcox had a short stint in a Cooper back in '06 in STX. It couldn't hang with the WRX (at that time) so he aborted it. (one example is Walnut Ridge NT in '06)

I'd love to see some more diverse cars in STX. a JCW Mini and Mazdaspeed 3 would be nice to see developed for the class.

[BlackbirdM3]

Welcome to the thread! It has been a while since I have done a UFO event, but I may this season just to get some testing in at Marina. I also hope to make most AAS events down there as well. I would also suggest running with BMWCCA, they put on nice events at Marina as well. Definitely come on out to SFR SCCA events though...we are going to have a great STX class this year!

What size RS3s do you have? Do you know what the spring rates are? Are the rear Koni shocks adjustable, & if so what setting are you running them at? What tire pressures are you running? What sway bars do you have currently? My car is pretty much the opposite in it's current set-up...I'm constantly chasing the back of the car, especially from mid-corner out. My car does have about -2* front camber though, due to offset bushings & a good alignment (thanks Edge Motorworks!), so that will definitely help if you can get more front camber.

The consensus I am getting is that the E30's like a lot more spring rate in the back of the car, I plan to run something like 650 front & 800 rear with no rear bar. I'm just not sure how that would apply to the E30 M3, those cars have a different balance to them, & less weight over the front axle. I'm not sure if you frequent bimmerforums or not, but Chris Conant is on there, he has arguably the most successful E30 M3 in SCCA autocrossing. I'm sure he will share some ideas about suspension set-up, he has been running that car a long time.

Hopefully I will see you out there one of these days, look me up if you see me, I would be glad to help in any way possible!

Thanks for the reply, my sway bars are stock, I haven't been able to find anything out about the spring rates, I've emailed Racing Dynamics and not gotten a reply. Reading between the lines, they are about the same as the H&R sport springs but sit lower. I'd like to bring the car up a little to improve the suspension geometry. I'm running 225/45/15 RS3s on the stock wheels, no room to add roll center spacers. The rear Konis are set full hard, but those are going away this afternoon for a set of TC Klein tuned ones, and the front Bilstein sports are going away and being replaced The TC-Klein Konis as well. I've got the Ground Control Camber plates and treehouse control arm bushings all sitting in a box waiting to go on the car this weekend. I need to get this sorted out before my 2nd race of the season next weekend.

I'm not a big fan of scca since I'm already an HSR-West license holder. I don't have any interest in spending a huge amount of money on race group memberships that don't do me any good for most of the time. I occasionally run with the PCA (The Golden Gate chapter doesn't like me, I made all the GT3 owners look bad when I spanked them with my Datsun a couple years ago. I was 13th of 133 drivers, and the 2nd fastest street car next to a GT2 on V710s that were big enough for me to sleep on. They asked me not to come back. I usually run with the Redwood Chapter at the Santa Rosa airport)
I'd like to see what BMWCCA has to offer, but it depends how much the membership is.

Any suggestions on the front end alignment settings?

Thanks,
Will

[race2win]

race2win,

Thanks for this thread. I'm a dedicated MINI JCW pilot starting my third year of autox. I stumbled across your thread looking for ideas. I had a "STX Prep" thread on Motoring Alliance last year for MINI drivers that several folks found useful. I started one a couple of weeks ago for 2012 referencing your thread. Here's mine:

http://www.motoringalliance.com/forums/autox/11732-scca-stx-2012-r56-class-prep-introduction.html#post113110

Though I'm not really planning on going to Nationals this year I like to think I will one day. Not a single MINI was entered in STX at the Nationals and the R56 is certainly not an ideal platform for STX. So I really like your effort to take the "underdog" E30 as far as you can go. Way cool! Much of your discussion and ideas are applicable to our little beasts so I thought I'd just let you know some of us are paying attention.

Good work.

Welcome, thanks so much for the kind words! A couple of minor corrections though... ;) As much as I would love to say I have won a National Championship, it's not so. I have won National Tours & Pro Solos, the traveling series that goes around the country all year, but believe it or not in my 20 year career I have never made the trip to the National Championships. I also wanted to point out that there was an E30 325i just like mine at Lincoln last year, it was driven by Doug Hitchcock, a member here (110stx).

I must say that I apologize...I left out the Mini S on my list of potential "cars-to-have" for STX. Definitely do NOT give up hope on the Mini's potential to succeed, that car has all the right ingredients to do VERY well! This is what makes STX so great...the vast array of different cars that have a chance at winning. The Mini is most likely going to be a course-dependant car like the E30, they are light & pretty narrow, & they turn very well.

Fat Cat Motorsports, the Miata Bilstien Guru, just finished building the suspension for a Mini JCW in STX that will be competing locally. So it appears my region may be one to watch this year as we will have many different top-prepped cars such as my E30, an E36 325is, RX8, Mazdaspeed3, Boss Mustang, & a couple WRX's ...& those are just the cars I know of! Our first event is Feb 19th at the Oakland Colesium, even though my suspension will most likely not be done yet, I cannot wait!

[race2win]

Wow, great thread. I've just started autoXing my E30 M3 with NorCal UFO. My current setup really sucks. Bilstein sports up front with Koni sports in the rear. The springs are Racing Dynamics, but I don't have a clue as to what the spring rate is. That said, the car does not rotate at all. The back end is very well planted and eventually overwhelms the front end about mid corner. It turns in fine, but if I get on the power early it becomes less inclined to turn. I've been autoXing since '06 with a VERY tail happy Datsun roadster (190+ hp, less than 2000 lbs, and locking diff with a live axle and leaf springs and very little weight in the back.) and going to the M3 is proving to be challenging. I'm guessing the spring rate is a little soft, but it feels like I need more front camber (its eating the outsides of the front tires, Hankook RS3s, and leaving the insides untouched) and perhaps more caster. What do these things like in terms of camber, caster, and toe? I have a set of custom valved Koni sports, treehouse racing control arm bushings and ground control camber plates on order. I'm not sure where I should set it up however. I'm thinking -2 degrees camber, 0 toe, and as much caster as I can run (I can't feel the car at all. I'm thinking of dumping the power steering, its WAY overboosted for my liking.). I'll likely end up installing a set of H&R race springs to both raise the front end up some (improving roll center), and adding some spring rate to help make it rotate. I was thinking of adding a big rear sway bar, to get it to rotate, but that has its drawbacks as well. I'm totally fine stepping the back end out, and catching it, I've gotten really good at that with the Datsun.

I'd love to hear any thoughts. In the cars first outting, it was the fastest BMW there, and it was totally undeveloped. The class I run in is perhaps the most highly competitive class that runs out there. I'd like to do better than a somewhat distant 4th place against cars that are 20 years older than it.

Thanks,
Will

Welcome to the thread! It has been a while since I have done a UFO event, but I may this season just to get some testing in at Marina. I also hope to make most AAS events down there as well. I would also suggest running with BMWCCA, they put on nice events at Marina as well. Definitely come on out to SFR SCCA events though...we are going to have a great STX class this year!

What size RS3s do you have? Do you know what the spring rates are? Are the rear Koni shocks adjustable, & if so what setting are you running them at? What tire pressures are you running? What sway bars do you have currently? My car is pretty much the opposite in it's current set-up...I'm constantly chasing the back of the car, especially from mid-corner out. My car does have about -2* front camber though, due to offset bushings & a good alignment (thanks Edge Motorworks!), so that will definitely help if you can get more front camber.

The consensus I am getting is that the E30's like a lot more spring rate in the back of the car, I plan to run something like 650 front & 800 rear with no rear bar. I'm just not sure how that would apply to the E30 M3, those cars have a different balance to them, & less weight over the front axle. I'm not sure if you frequent bimmerforums or not, but Chris Conant is on there, he has arguably the most successful E30 M3 in SCCA autocrossing. I'm sure he will share some ideas about suspension set-up, he has been running that car a long time.

Hopefully I will see you out there one of these days, look me up if you see me, I would be glad to help in any way possible!

[GreyLens]

race2win,

Thanks for this thread. I'm a dedicated MINI JCW pilot starting my third year of autox. I stumbled across your thread looking for ideas. I had a "STX Prep" thread on Motoring Alliance last year for MINI drivers that several folks found useful. I started one a couple of weeks ago for 2012 referencing your thread. Here's mine:

http://www.motoringalliance.com/forums/autox/11732-scca-stx-2012-r56-class-prep-introduction.html#post113110

Though I'm not really planning on going to Nationals this year I like to think I will one day. Not a single MINI was entered in STX at the Nationals and the R56 is certainly not an ideal platform for STX. So I really like your effort to take the "underdog" E30 as far as you can go. Way cool! Much of your discussion and ideas are applicable to our little beasts so I thought I'd just let you know some of us are paying attention.

Good work.

[BlackbirdM3]

Wow, great thread. I've just started autoXing my E30 M3 with NorCal UFO. My current setup really sucks. Bilstein sports up front with Koni sports in the rear. The springs are Racing Dynamics, but I don't have a clue as to what the spring rate is. That said, the car does not rotate at all. The back end is very well planted and eventually overwhelms the front end about mid corner. It turns in fine, but if I get on the power early it becomes less inclined to turn. I've been autoXing since '06 with a VERY tail happy Datsun roadster (190+ hp, less than 2000 lbs, and locking diff with a live axle and leaf springs and very little weight in the back.) and going to the M3 is proving to be challenging. I'm guessing the spring rate is a little soft, but it feels like I need more front camber (its eating the outsides of the front tires, Hankook RS3s, and leaving the insides untouched) and perhaps more caster. What do these things like in terms of camber, caster, and toe? I have a set of custom valved Koni sports, treehouse racing control arm bushings and ground control camber plates on order. I'm not sure where I should set it up however. I'm thinking -2 degrees camber, 0 toe, and as much caster as I can run (I can't feel the car at all. I'm thinking of dumping the power steering, its WAY overboosted for my liking.). I'll likely end up installing a set of H&R race springs to both raise the front end up some (improving roll center), and adding some spring rate to help make it rotate. I was thinking of adding a big rear sway bar, to get it to rotate, but that has its drawbacks as well. I'm totally fine stepping the back end out, and catching it, I've gotten really good at that with the Datsun.

I'd love to hear any thoughts. In the cars first outting, it was the fastest BMW there, and it was totally undeveloped. The class I run in is perhaps the most highly competitive class that runs out there. I'd like to do better than a somewhat distant 4th place against cars that are 20 years older than it.

Thanks,
Will

[race2win]

A valid point. Ever see the GRM article where they tested heavy verses light wheels? Didn't really affect the times, but it wasn't quite a full 30lb increase.

You can't just factor weight. If you're adding better gearing (saving 2-3-2 shifts) and a wider contact patch, it may overcome the weight deficit. May...

Agreed...potential benefits of the 17s are slightly wider contact patch & better gearing for longer courses. Downside is more un-sprung weight & taller gearing on shorter courses.

Going to a 7.5" wheel is an even more unfair comparison. You'll need some data to really see if you're picking up gs and or time in sections with the taller/wider combo. That's my point. test cheap, if it shows merit, then you can get lighter wheels or perhaps even find some with just a little more width to them too.

The ARC8's are actually 17x8s, which is the ideal 17" size for an E30 IMHO. I feel that size/weight wheel with 235 Star Specs is about as close as possible to a fair comparison to my 15x8/225 set-up to determine if those benefits mentioned above are reality. The problem with the heavy 20lb wheels is that I will always wonder how much time I would be giving up due to the extra weight. But I agree, testing as cheap as possible is ideal.

Good plan. I have been loving the Toyo R1-R in the rain fwiw. I beat Matt McCabe (2 time CSP champion) raw in Lincoln last year in an STS CRX in the wet.

Nice! That's no small feat, Matt can wheel with the best of them. I know some of the CSP guys well...Scott Fraser & Ruben Padron (in the ex-Palmquist car) are good friends, we all have great times battling for top PAX here locally :).

The R1R's are definitely a great choice in the wet, especially on the smaller/lighter cars. However, there is a LOT of chatter in the Street Touring world right now about the new Michelin & how good it may be in standing water. Last year, IIRC, most people with the larger/heavier cars ran either the Continentals or Star Specs in the wet.

[GotCone?]

19.8 lbs is VERY heavy, even for a 17. After you factor in the extra weight of the tires, my car would gain around 30 lbs over all compared to my current 15x8 set-up...& I don't have the lightest 15x8s out there. I believe 5-10 lbs difference is just noise...30 lbs however will show up on the watch.

A valid point. Ever see the GRM article where they tested heavy verses light wheels? Didn't really affect the times, but it wasn't quite a full 30lb increase.

You can't just factor weight. If you're adding better gearing (saving 2-3-2 shifts) and a wider contact patch, it may overcome the weight deficit. May...

I see benefits to a 17" package as I have mentioned before, I hope to do some testing this summer to see if they are indeed faster. However, going with heavy wheels such as the XXRs may provide false information, if I am going to do it I would rather spend extra on the Arc8s so that I am within that "noise" to get an accurate comparison.

Going to a 7.5" wheel is an even more unfair comparison. You'll need some data to really see if you're picking up gs and or time in sections with the taller/wider combo. That's my point. test cheap, if it shows merit, then you can get lighter wheels or perhaps even find some with just a little more width to them too.

Depending on the results of that testing & budget permitting, if/when I go to Lincoln this year I would like to bring 3 sets of tires/wheels...

1. My current 15x8 225/45-15 RS3 set-up - great gearing out of corners, light, best warm/hot weather tire, should be the best in tight stuff & transitions.
2. Light 17x8s with 235/40-17 Dunlop Star Specs - great all around tire, will work well in colder temps and/or damp, slight width gain over 15s, & will provide a gearing bump for those longer courses.
3. Either Continental ExtremeContact DWs or Michelin's new Pilot Super Sport for standing water/wet sitiations, as both will provide better wet grip than the Dunlops, & especially the Hankooks. These would also double as street tires for the car to drive to & from events, & general weekend use. I just wish they made something smaller than a 17 in the new Michelin...

Good plan. I have been loving the Toyo R1-R in the rain fwiw. I beat Matt McCabe (2 time CSP champion) raw in Lincoln last year in an STS CRX in the wet.

[GotCone?]

I was running on Kumho Ecsta XS's. Switching to Hankooks this year, but will still run the same size. The Hankooks are better and cheaper. win-win.

255s will be pinched on an 8.25" wheel. I'd be curious to see your actually measured section width. 255s on a 9" wide just barely fit up front in an E30 M3, trust me I know from experience ;) The skinnier wheel may help fitment some, but stuffing a wider tire will hurt responsiveness, especially with those XS.

[GotCone?]

I would love to work on the car with you. You know that. In a freakin' HEARTBEAT, bro'.

However, I would rather bring the car to you and see how it works at LAP, as that's better than tuning it for MCC.

dh

Well then. Rand and I may have just made testing easier for you. We've been needing a rain set for the E30 project and have settled on that this weekend. 17x8.25 XXR 530s wrapped in 245/40-17 Hankook RS-3. Wheels are pre-order, so not sure when we'll have them and the tires all mounted up, but I'm sure we can give them a try on your car Doug.

I'll post up pics once I have them mounted and if they show up in time before I start to modify the fenders, I'll get pics of them on the E30 as it sits today.

Thanks - Jon