Autocross and understeering pig ZX3

[Garsdad]

I went through an autocross school this weekend- first time in 15 years that I have autocrossed. It was pouring down rain, so I was able to uncover some demons in the stock ZX3 set-up- cheif among them horrendous understeer. I tried a little tuning with tire pressure, but couldn't get much of a handle on it.

I would like to run showroom stock (I'm a cheap bastard) so I can't get too involved in modifications.

If anyone has successfully tamed the beast with Showroom Stock legal items, I would like to hear about it. My tires are the stock ones that came on the car (2002 ZX3) and I realize that replacing those would help, but I think that improving the balance of my car with the zero-grip tires that are on it will only make it fly with some sticky rubber.

Also, does anyone know if I can upgrade to SVT suspension pieces and more specifically wheel and tire size under Showroom Stock rules? What about the 6-speed (I really want limited slip, and that might be a "rule-friendly" way to get it).

Thank you for any and all help.

By the way, if you have a chance to take an autocross school in the rain, do it! You can't hide from your or your car's shortcomings, and you reach the limits in each and every corner. I really learned much more than I could have if the car had enough stick to mask my chunky driving. It was "forced smoothness".

[Demon4545]

I can't speak for the rules of your organization, but i'm almost certain that the SVT six speed doesn't have a limited slip...either way, you're looking at an aftermarket one.

[Egz]

If Showroom Stock is anything like HS or GS, no, you won't be able to put a SVT suspesnion on it, since its a different model and not a trim level.

[bwojdyla]

if you really wanted to go through the hassle, you could have your camber altered to to sit on the extreme edge of the factory specification. some negative camber up front would probably help if you could manage to narrow the track in the rear a little bit.

While the understeer exists, I can say that its extremely predictable. I was doing some incredibly hard driving in west virginia and the transition to understeer was both predictable and controllable (good thing too, there was a drop off the back of the mountain). had to stop eventually because of brake fade. oops.

I've actually managed to induce oversteer in a double 90 chicane, not in wet conditions though. Yeah, I think with a combination of negative camber and tire pressure management you can get the car much closer to neutral steer, although I think its probably a futile pursuit to tryand get it all the way there in the showroom stock class.

[Garsdad]

Thanks. I thought the SVT had LS... seems silly not to!

I would be happy with a little closer to neutral. I used to have an Alfa Romeo that was so easy to balance and tune... of course, it was not stock anymore, either.

My biggest issue was having to slow so dramatically for a hard corner, then being unable to get on the throttle coming out due to the wheelspin. I have not checked my car- is the toe-in on the rear adjustable?

[2004SVTAutoXer]

if the SVTF had the LS i'd be in heaven =/

[RecoilRob]

There is a spec for the rear toe so I am assuming that it is adjustable but haven't played with mine yet. The front toe is your most likely place to help your turning ability. Toe the thing out 1/4 turn on each side and see how it feels. You will instantly find the car turning easier and more aggressively. Keep toeing it out until you start to slow down. Simple to do and it costs nothing.

Seriously, take your wrenches with you on your next track day and play with the front toe settings. You will find that the stock setup is NOT the fast way around the track.

[rschumin]

horrendous understeer. I tried a little tuning with tire pressure, but couldn't get much of a handle on it.

I'm running an '04 ZX3 in SCCA HS. Shocks and a cat-back are the only mods. BTW I am also using R-comp tires, but what I'm going to say applies to street tires too.

The laws of physics dictate that front wheel drive cars will understeer. You can mitigate that somewhat with suspension modifications, settings, and tire pressure. You can also loosen up the back to get the car to rotate with tire pressure, shock settings, and trail braking.

"Horrendous understeer" is almost always driver induced. You just have to condition yourself in to slow down when you enter a turn, get the car to turn, and then power out. Slow in, fast out is the key.

Ray
'04 ZX3 2.3
BRR-SCCA
#42 HS

[beatfocie]

i up graded to svt sus. and the car is pretty well balaced i get a bit more over steer when pushing the limits of the stock 15s

[Daeron]

Tire pressure will help you out quite a bit. Chalking your tires will help you get in the ballpark. Pyrometer will help you fine tune. Don't be afraid to get some new rubber for racing

Side story: I went to the local autox this last weekend. There was a Civic Si there and I had to laugh the entire time it was out there. Nothing but screech no matter what that car was doing on the course. It was almost as funny as the old VW Rabbit GTI that was out there backfiring at almost every corner