Here's my problem: understeer.

Here's setup on my car: RB front bar, Dunlop Super Sport Race r-compounds in 225/40/18.

Alignment (performed by an excellent shop w/ drivers seat weighted):
front camber: -1.1 (max they could get)
caster: max possible after camber.
rear camber: -1.5
toe: zero front and rear.

Best pressures I found yesterday were 37 front, 46 rear. Those pressures may seem high, but chalk on the fronts indicated good utilization of the shoulder. Even with this setup, the car still did not want to rotate. Once in understeer, I tried using smooth throttle modulation, abrupt throttle lifts, abrupt throttle stomps, smooth brake application, and brake stabs. None of these really helped to rotate the car in the first 1/3 of the corner where I feel it needs it.

I should mention that I am not trail-braking at all, and my times were pretty quick, so I feel like my biggest limitation right now is not being able to get the car neutral. Some may suggest returning to the stock front bar. I feel like the RB bar has increased my slalom speeds dramatically, but I do agree that it is less forgiving of excess speed at turn-in than stock.

Looking for any setup tips, or driving technique tips from some of the faster guys on here. Suggestions? I haven't changed shocks yet, which I'm sure would help. Would going to Koni SA's get the car more neutral? I'd really like to get the car to have a slight oversteer and then tune with pressures and technique. Thanks in advance.

 

Less camber in the rear, maybe some toe out in the rear too since you don't trail brake. I was able to get -1.4 in the front on both sides for camber (also with a little toe out).

The front bar definitely (IMHO) helps in the quick transitions... I noticed a big improvement anyways. To take care of the pushing, I have been known to run 55 psi in my rear tires (V710s) depending on how tight the course is... even with less camber.

My shocks should be going in within the next week or two, and I hope I'll be able to dial out the push with them.

--kC

 

That's funny, when I got my alignment, I actually requested fronts set to max negative camber and rears set equal to the fronts. The alignment shop, who is highly regarded, didn't want to do that for a car that is driven on the street (I don't have the benefit of a dedicated autox car). I'm second-guessing their opinion now. I think I was probably right to begin with, plus with the DSC turned on, the car should be just fine on the street. Anyway, I think I will try 50+ in the rears next time out. I know you're on Kuhmo's, but what were your front pressures? I had to quit trail-braking when I went to the bigger front bar to prevent understeer; on the stock bar and stock tires, I could trail brake most turns without problems.

 

my experience was it was easy to get on the front bump stops while braking, then it would just push and push and push. stay off them it and it turns nicely, but trailbraking would get the car turned enough i could keep it turning with the throttle.

trailbraking is better!

james

 

We have been running 41f and 39r pressure running 265 Kumho ecsta. The front has 1.1 deg camber and the rear at 1. Also running a RB front bar. The car transitions great but tends to understeer if you are not careful getting into a sweeper. Part is the soft springs in the front and under heavy braking (I use the ABS to my advantage) sometimes it gets hard to trailbrake into a corner. I have been used to doing trailbraking while the ABS is kicked in, it was in a ESP prepped Cobra.
The thing to watch in this car (in my opinion) is the watch your entry speeds. The car likes to understeer and will if given a slightest chance. I think the only way to correct it in stock car is to make a change in driving style.

Just my opinion after putting a few events under my belt in the 8

 

once i cut the front bump stops the understeer problem went away. its not legal in some classes so check first!

james

 

Last year I had the RB front bar. At the time I thought it helped reduce push. With the new car this year, I started out driving an autox with no modifications to get a baseline, and I must say I think the stock front bar allowed the car to turn in a bit crisper.
If you still have your stock front bar, you may want to try swapping it back to find out if your car gets more neutral.

 

For those of you who are getting -1.5 degrees of camber in the front, how
are you getting that much? Luck of the draw? Are there any suspension
connections I can loosen to try to get any slop in my favor?

Any suggestions you have would be appreciated.

 

not sure why a stiffer front sway on the rx8 should reduce push. its not a strut style suspension with inadequate camber gain, and there isnt excessive body roll (for a stock suspension anyway).

james

 

Ed, I've gotten the impression that there is a lot of variability...in what each car allows and/or the skill of the person doing/checking the alignment. bmc got -1.5 on his first alignment last year but was only able to get -1.0 or -1.1 the second time he put it on the rack. From what people have reported here, there sems to be a bell curve with -1.0 and -1.5 at the extremes and -1.2 and -1.3 being much more common.