Autocross Setup Advice Please.

[CatchM3IfYouCan181]

So I just got started on autocross this year. I have a 2008 E92 M3 which I've been running for most of the season. Right now, I'm running on my stock rims which are 19x8.5/19x9.5 and RE-11 road tires but as the season comes to a close, I'm already planning on what to do next.

What I have in mind: KW Variant 3's, 18x10's squared and Hoosiers A6's. I also plan to put in headers and intake.

Just installed a Borla ATAK exhaust and I plan to put in the Evolve tune in it.

Any suggestions would be greatly appreciated.

[warp10]

go with apex arc8 or ec7's wheels they are the best for the money.

[Richbot]

Do you have a specific class and sanctioning body in mind? If you're running with the SCCA, those modifications will bump you up a few classes. I have been running in Stock class all season and the car is a blast on an autocross course within the Stock-class rules, I definitely recommend it.

If you don't care about class and just want to mod the car, it really just comes down to what you want to do to it.

[CatchM3IfYouCan181]

Originally Posted by warp10motorsports

go with apex arc8 or ec7's wheels they are the best for the money.

what do you think of the kumho's? any other advice as far as wheels? I was thinking of throwing in spacers? 10mm to 12mm.

[CatchM3IfYouCan181]

Originally Posted by Richbot

Do you have a specific class and sanctioning body in mind? If you're running with the SCCA, those modifications will bump you up a few classes. I have been running in Stock class all season and the car is a blast on an autocross course within the Stock-class rules. If you don't care about class and just want to make the car faster, it really just comes down to what you want to do with the car.

I'm probably running ASP next season. I knew I forgot to mention something, thanks for pointing it out.

So I'm running SCCA, MSNE & BMW CCA although I'm mainly competing in SCCA so ASP is my target. I've been running AS RTR.

I also am trying to consider whether to go with the KW V3's paired with Vorschlag Camber set vs the KW Clubsport, any thoughts on this?

[Richbot]

For ASP and autocross in general, the biggest bang for your buck is going to be fitting as much tire under the car as possible. My Stock-class car fits the 295/30-18 and 315/30-18 Hoosier A6 under it on the stock wheel widths, so that's your starting point. Several people have used 285/30-18 A6's square on 18x10's if you want to do something that's proven to work, but this car needs more rear tire than that on an autocross course. If I were building a full-tilt ASP car I'd find a way to get the 315/30-18 Hoosier to fit up front, which would probably mean custom 18x10.5's and some new fenders, and the 335/30-18 in the rear on 11.5's would fit with some small fender modifications, but you're probably not interested in going that far. You might also consider the BFG R1-S, they are about $200 cheaper per set than the Hoosiers and offer very similar performance, and the 285/30-18's are wider than the 295 Hoosier which might be a good compromise if you want to run square.

The next place to look is a GOOD set of coilovers with some much stiffer springs. I'd look past KW to a Motion Control Suspension, JRZ, or Moton setup if it were my money. There's no reason to bother with an intake or headers on this car, they make next to no power and save no weight either, so use the money you save on not pointlessly modifying the engine in the suspension. Key here will be maintaining tire clearance, because tire/weight is arguably the most important thing in autocross after thrust/weight. Many coilover setups eat into tire clearance in the front with the adjustable spring perch. Motion Control for sure can make a setup that will actually improve tire clearance to the strut, not sure about anybody else. I don't know anything about the KW Clubsport so I can't help you there.

Next, I'd focus on getting weight down. Seats, a lightweight battery, and the wheels you buy should be worth in the neighborhood of 150lbs, and more can be lost in the exhaust as the Borla system and stock midpipe both weigh quite a bit compared to some of the race parts out there

If you're getting the Evolve tune I would keep the stock redline rather than opt for the increased rev limiter, 70mph is plenty and you'll be banging against the limiter enough that I wouldn't want to add any extra stress. I'm usually on the limiter in 2nd at least once per event even on tighter courses

[Porschefile]

Originally Posted by CatchM3IfYouCan181

I also am trying to consider whether to go with the KW V3's paired with Vorschlag Camber set vs the KW Clubsport, any thoughts on this?

Both are good coilovers. The Clubsports have stiffer springs and valving, and work somewhat better on track (or AX). IMO you'd definitely be better off with the KW CS if you're going to buy camber plates anyway. Camber plates are $500 and the price diff between V3 and CS is only like $1k and you get better springs and valving along with the plates.

For a blank check build I'd get motion control or moton probably, something with remote reservoirs.

[CatchM3IfYouCan181]

Originally Posted by Richbot

For ASP and autocross in general, the biggest bang for your buck is going to be fitting as much tire under the car as possible. My Stock-class car fits the 295/30-18 and 315/30-18 Hoosier A6 under it on the stock wheel widths, so that's your starting point. Several people have used 285/30-18 A6's square on 18x10's if you want to do something that's proven to work, but this car needs more rear tire than that on an autocross course. If I were building a full-tilt ASP car I'd find a way to get the 315/30-18 Hoosier to fit up front, which would probably mean custom 18x10.5's and some new fenders, and the 335/30-18 in the rear on 11.5's would fit with some small fender modifications, but you're probably not interested in going that far. You might also consider the BFG R1-S, they are about $200 cheaper per set than the Hoosiers and offer very similar performance, and the 285/30-18's are wider than the 295 Hoosier which might be a good compromise if you want to run square.

The next place to look is a GOOD set of coilovers with some much stiffer springs. I'd look past KW to a Motion Control Suspension, JRZ, or Moton setup if it were my money. There's no reason to bother with an intake or headers on this car, they make next to no power and save no weight either, so use the money you save on not pointlessly modifying the engine in the suspension. Key here will be maintaining tire clearance, because tire/weight is arguably the most important thing in autocross after thrust/weight. Many coilover setups eat into tire clearance in the front with the adjustable spring perch. Motion Control for sure can make a setup that will actually improve tire clearance to the strut, not sure about anybody else. I don't know anything about the KW Clubsport so I can't help you there.

Next, I'd focus on getting weight down. Seats, a lightweight battery, and the wheels you buy should be worth in the neighborhood of 150lbs, and more can be lost in the exhaust as the Borla system and stock midpipe both weigh quite a bit compared to some of the race parts out there

If you're getting the Evolve tune I would keep the stock redline rather than opt for the increased rev limiter, 70mph is plenty and you'll be banging against the limiter enough that I wouldn't want to add any extra stress. I'm usually on the limiter in 2nd at least once per event even on tighter courses

wow. this was a great response. thanks very much for the input.

I look forward to trying it out.

[CatchM3IfYouCan181]

Originally Posted by Porschefile

Both are good coilovers. The Clubsports have stiffer springs and valving, and work somewhat better on track (or AX). IMO you'd definitely be better off with the KW CS if you're going to buy camber plates anyway. Camber plates are $500 and the price diff between V3 and CS is only like $1k and you get better springs and valving along with the plates.

For a blank check build I'd get motion control or moton probably, something with remote reservoirs.

I was thinking Moton's but I didn't know if autox would require everything the Moton's gives. plus it's custom and i wouldn't know what specs to give them as I said, I'm still very much a newbie. So whether I could afford it or not would just making me dumb for spending on the wrong specs, right?

[Richbot]

If you've never done anything with suspension on the level we're talking about with a Moton or other remote-reservoir, I would think the KW CS would be more than enough for you to play with to start out.

[CatchM3IfYouCan181]

Originally Posted by Richbot

If you've never done anything with suspension on the level we're talking about with a Moton or other remote-reservoir, I would think the KW CS would be more than enough for you to play with to start out.

my thoughts exactly. My dad who coaches me told me the same thing when I told him I was gonna spend 8000 on Moton's. his first reaction was wow and then wait a minute, you need to have the feel for suspension to know what to ask for. Thank you Richbot. my brother actually linked me to a bunch of threads from you when I first started autox

[CatchM3IfYouCan181]

Originally Posted by Richbot

If you've never done anything with suspension on the level we're talking about with a Moton or other remote-reservoir, I would think the KW CS would be more than enough for you to play with to start out.

decided to go with an 18x10 squared set up with RS3's to continue to develop my driving skill (figure i might get spoiled on Kumhos or Hoosiers). I'm also gonna throw in the KW Clubsport which includes camber settings so I can get as much negative camber as possible.

[Richbot]

Sounds good, running in STU makes more sense for someone who is just getting started but still wants to modify the car, and so far you're good to go with the STU rules (285 max tire width, unlimited wheel width), and all of the other stuff you've listed is legal in STU as long as you keep some form of catalytic converter, might want to read the rules on changing cats as they've been changed a few times and I'm not up to date.

[CatchM3IfYouCan181]

Originally Posted by Richbot

Sounds good, running in STU makes more sense for someone who is just getting started but still wants to modify the car, and so far you're good to go with the STU rules (285 max tire width, unlimited wheel width), and all of the other stuff you've listed is legal in STU as long as you keep some form of catalytic converter, might want to read the rules on changing cats as they've been changed a few times and I'm not up to date.

yea i kept that stock. I've won the last few events just by adding camber so I figured these few mods so I can be in STU will good and a lot of seat time.
Thanks for the advice. Keep you updated.