understeer! looking for advice to balance looks + neutral behavior

[SECRET M]

i'm currently using stock EDC dampers + rdsport springs + 15mm spacers up front & 12mm spacers rear. i'm using stock 18s with PS2s.

this weekend was the first time in a long time that i've did some spirited mountain driving, and i found the car understeering pretty heavily. i realize the rdsport springs are way to low (cracked the TPMS sensor covers under the bumper at least 3x now..), and i'm not sure the spacers are helping either.

i'd like to bring the suspension behavior back to neutral, but without giving up on the looks department too much. the car really has a nice stance right now and rides and behaves very well for most street driving.

looking around online, i see some popular items:

-Ground Control Adjustable Springs + Camber Plates

-KW Adjustable Springs

-Dinan Stage 3 Suspension

is the fix i need a simple camber adjustment up front or am i just too low? would appreciate advice from anyone who has some legitimate suspension tuning experience. would prefer not to hear 'swap out your springs for H&Rs.' i realize going back to stock may fix the understeer issue, but doesn't address what i'd like.

thanks in advance.

[Matei]

If the front is to low, then all the weight on the front axle will induce understeer as the mass will transfer on the front axle in corner entry. Is strictly a mass transition issue. You can help with this by lowering the rear too and a more negative camber up front, this if you want to keep the car low and still have grip.

[SECRET M]

Originally Posted by Matei

If the front is to low, then all the weight on the front axle will induce understeer as the mass will transfer on the front axle in corner entry. Is strictly a mass transition issue. You can help with this by lowering the rear too and a more negative camber up front, this if you want to keep the car low and still have grip.

good point. i think the rdsport springs actually add rake which may be adding to the issue. are you using any aftermarket springs/coilovers?

[kitw]

This isn't a weight balance issue, check how much camber you have. If you haven't already, pull the pins up front, with the RD sport springs you should be at -2 to -2.4 degrees of camber. That will kill some of the understeer.

Next step is going to a square tire setup.

[Matei]

Originally Posted by SECRET M

good point. i think the rdsport springs actually add rake which may be adding to the issue. are you using any aftermarket springs/coilovers?

I just have experience with suspension setups, as I race in formula cars. This is my opinion besed on my experience. I have on my car h

[Matei]

Sorry, I'm on my mobile application.

So I have on my car h&r springs. I find the car very well balanced.
I do run a quite negative camber on front and the corner entry is very good. About the exit, the car has a lot of grip as long as the acceleration is progressive as I run 285 tires in the back. I think it all depends of the driving style.
If the corner entry is done correctly ( brake hard initially then wait a bit until the apex and then push the gas progrresivly the car will be well balanced).
The mass distribution is also a factor, but as I said it all depends about the driving style. If the car is driven hard in corner entry and the apex will be overshot with more speed it will always have understeer.

[kitw]

I think you have to remember how little travel the front suspension has. The RDsport springs drop the car onto the front bumpstops, which means the effective wheel rate is REALLY high. this is going to lead to understeer pretty much no matter what.

Switching to H&Rs or Eibachs with shaved upper guide supports is one way to fix it. Additional negative camber won't really help with the RD sport setup. KWs or Ground Controls or the KW sleeve kit might help too. All depends on how much money you want to spend and how much track time you'll actually do. The KW sleeve kit is pretty soft for track work, but the shorter stops they include will at least keep you off the bump stops.

[SECRET M]

Originally Posted by kitw

I think you have to remember how little travel the front suspension has. The RDsport springs drop the car onto the front bumpstops, which means the effective wheel rate is REALLY high. this is going to lead to understeer pretty much no matter what.

Switching to H&Rs or Eibachs with shaved upper guide supports is one way to fix it. Additional negative camber won't really help with the RD sport setup. KWs or Ground Controls or the KW sleeve kit might help too. All depends on how much money you want to spend and how much track time you'll actually do. The KW sleeve kit is pretty soft for track work, but the shorter stops they include will at least keep you off the bump stops.

if i were to keep the RDSport springs, change out the bump stops for shorter E36 bump stops, and install GC camber plates set at -2.0º, what is the difference between that set up and swapping out to the full GC kit with the car set to the same height as my RDSports but with -2.0º front camber and shorter bump stops?

[kitw]

^ I don't think GC has a camber plate setup that works with stock diameter springs. I know they have made them for other cars, but at that point, you might as well just buy their whole kit and sell your RD sport setup.


You can get -2.0 degrees of camber out of stock upper guide supports, btw. You'll need to go to camber plates to reduce the stack height for more travel.