Dialing out oversteer (Race video on page 2)

[MisterMiniS]

I know there are a TON of ways to go about this, but I am looking for effectiveness, ease, and cost.

Anyways, on an autocross course, I tend to have more oversteer than I should. I can change driving habits to counter that, but it generally make me slower. Please school me on suspension setup. My setup and thoughts are below.

- GC coilovers. Ride height set to the middle of the collars. Front 550, rears 875 (wow, so high you say).
- Front shock stiffness set to middle
- Rear shock stiffness set to high (seemed to help more than when it was set to as low as possible...does that even make sense?)
- Pressure in the rear usually 2psi over fronts (fronts heat up much more).
- GC camber plates with roughly -4 degrees of camber.
- Removed stock rear sway bar
- have stock front sway bar

My thoughts/plans:

Option 1
- Keep 875 springs in the rear and put a 25 mm sway bar on the front
- Basically the logic is to make the front as stiff as possible to help the rear stay planted.

Option 2
- Get different springs for the rear, maybe like 750's?
- Still put sway bar on front, but maybe 22mm instead of 25mm.
- Same logic I guess

I want to be able to throw the car into corners like I currently can, but not have the oversteer. My turn-in is awesome, and I want to keep it that way. Oversteer is currently not unmanageable, but if I try to put down a little power exiting a corner, I just end up trying to control a drift. Clearly, that is not the fastest way through and autox course. Through a slalom, the car stays neutral, so I hope that gives you a level of understanding.

I am by no means a setup expert, so please let me know the error of my ways / plans. Thanks. Also, the 875 rear springs were suggested by GC themselves. I was told to trust their suggestions, but maybe they went too high.
Thanks!

[Roland H]

Option 1: Buy an E36.
Option 2: Go with your original option 2.

But literally, the only way to fix the rear-end issue of the E30 without doing a ton of custom fab that will knock you out of DSP is to get an E36.

[blefevre]

Remove rear trailing arms. Insert some other suspension.

But in all seriousness start with your option 2.

[MisterMiniS]

I hear you, I really do, but it's not gunna happen anytime soon. That said, My retardedly under-prepped DSP car was not even 2.5 seconds off the pace of the top E36 DSP cars at PPIR. They run wide ass hoosiers, I run skinny Nitto's. I want to be able to get the car setup quite well without A6's and then just make that about the last thing I do.
That said, each year there is a super fast E30 in DSP that comes very close to winning nationals (and has before).

194/DSP Paul Leonard 95 BMW 325iS
1) 62.447 2) 61.029 3) 60.732 4) 61.706 DNF


94/DSP Evan Leonard 95 Bmw 325is
1) 0.000 DNF 2) 60.315 + 1 3) 60.875 4) 60.619 DNF


25/DSP David Jobusch 93 BMW 325 SSS
1) 61.767 2) 61.866 3) 0.000 DNF 4) 61.471 DNF


125/DSP Lee Michael 93 BMW 325 SSS
1) 62.053 2) 61.821 3) 62.077 + 2 4) 61.497 DNF


181/DSP Tom Pora 95 BMW 325is
1) 63.513 2) 61.485 + 1 3) 62.023 4) 61.866 DNF


30/DSP Matthew Stephenson 89 BMW 325i
1) 65.730 + 1 2) 63.936 + 1 3) 63.453 4) 63.118

Forget they are in X and the last run doesn't count. They can achieve it, so I counted it. I'm close, I'm in a E30, I'm very underprepped, I can catch them.

Ignore the fact that Mark Smith hit a 59 on this 4th run...ignore that.

[Jaxx_]

1) a slight sliding is the fast way
2) 875 is probably too stiff if you're running without a swaybar and still getting oversteer.
3) a smaller front bar will only worsen the oversteer.

what are your alignment settings?

I'd like to see how you're handling the car before you start modifying the suspension anyway... got videos of your steering inputs?

[MisterMiniS]

1) a slight sliding is the fast way
2) 875 is probably too stiff if you're running without a swaybar and still getting oversteer.
3) a smaller front bar will only worsen the oversteer.

what are your alignment settings?

I'd like to see how you're handling the car before you start modifying the suspension anyway... got videos of your steering inputs?

1) yessir...but it is more than slight at times (even without power)
2) agreed...750 sound better?
3) I have stock, going for 22 or 25
4) some changes since last alignment, so they aren't helpful right now. I'll try to get one soon (free car-lifetime alignments :p)
5) I have old videos, from when I first started racing. They are missing many mods, so those are not helpful. There is a race next weekend I will try to get a GoPro for and record my runs. I am new to racing, and to my car somewhat. Last year was my first year of autox, and of racing anything. I got kicked out of the novices for scoring too high enough times, so I guess that means I'm not terrible. :p
I do need a lot of practice racing, but that comes with time.

[Bimmerman325i]

My input: spring rates are way too high for an SA koni to effectively control. I would upgrade the rears to DAs or ASTs for better spring control. Similarly, bigger front sway. I would decrease rear rates a couple hundred pounds, and consoder adding a rear sway again. Buddy's e30 autox car out here has aftermarket sways and softer springs, and does not oversteer everywhere. Id also strongly consoder dA shocks of some sort, compression adjustment helps a lot.

[Bimmerman325i]

also....how much have you read through Vorshlag's 318is build? they figured out how to put power down by increasing rear droop through shock craziness. Granted, that was in an attempt to overcome the lack of LSD, but I would imaging that it would help put power down.

[Wh33lhop]

Take the rear rates down, and until then have fun. Oversteer is the best kind of steer.

[R3Z3N]

^^^Having more or less rear droop would not change on power handling.

Changing front droop affects on power steering.
Changing rear droop affects off power steering.

However, most likely you would be using much too soft of springs to get that much body roll fore to aft, this is of course unless you are limiting your shock travel quite a bit.

[fsmtnbiker]

I would start with a stiffer front swaybar. I don't think your spring rates are too stiff - Especially when dealing with the E30 rear suspension. It's best if it just doesn't move.

[clarkkey594]

I would start with a stiffer front swaybar. I don't think your spring rates are too stiff - Especially when dealing with the E30 rear suspension. It's best if it just doesn't move.

What Chris said.

[Franken30]

Several tips can be found at the bottom left of page 6 of the guide found here: http://www.tirerack.com/images/pdf/warranty/BFG2.pdf

Hope this helps.

[MisterMiniS]

Front sway bar on its way. I'll let you all know how it went on Sunday. Thanks for all the input.

[CO318is]

Which one did you get? We are looking at dialing our rear bar to soft for this event. We are also trying to figure out our front sway bar mounts. The pulled out the last event.

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