Jims5543

My AutoX setup sucks at higher speeds. I remember my first open track day. I used my tried and true AutoX suspension settings and the car was too loose.



I tried running w/o a rear swaybar. It seemed to rotate better in the slow turns but made the car too loose for the faster turns.



Now I just do like Mike said go in slow come out fast.

Fluid Dynamics

I've noticed that my FC understeers a lot more with higher steering angle (turn angle of the front wheels), and I think this relates to insufficient front caster. I'm going to play with adding a little more front caster on autox days. When it doesn't push at high speeds during turns, it will push badly at autox speeds for a given front negative camber setting. I've found that my best front traction for cornering at 40+ mph is had with about a degree of front negative camber, while I can't seem to get enough negative front camber dialed in for 20mph cornering (my strut tower slots max out at around 2 degrees).



Regarding pushing on turn entry: I like to think of this as "turn in understeer", and it can be overcome by entering the turn just as you're coming off the brakes and the nose of the car is coming up. This creates a very brief trail braking situation that loads up the front tires more than the back when they are turning in and naturally have a much higher slip angle than the rear tires, which haven't begun turning. Higher slip angle on the front tires = pushing and plowing, hence the ability to overcome understeer with more negative toe in the rear.



By doing brief trail braking on turn-entry, I have found myself to be able to use up my traction budget more of the time (be at the limits of the tires more often in a turn). Making a turn on a correct path, or line, on the edge of traction, requires a delicate balancing of the chassis in a certain way.

Fluid Dynamics

You got it. Softer spring, anti-sway bar, and shock rates in front, as well as higher tire pressure and less weight in front and some rear toe-in and mild front toe-out, and of course (probably the most important one for track events) adding some front negative camber will all reduce understeer. If you have wider tires in back than in front, this can cause more understeer than if the tires were the same size.



Regarding driving technique: I realized my biggest driving mistake and got much better after taking a couple trips around a course with the local FD top time guy. I swore he was going to spin the car a few times but his technique allowed him to keep it under control at a much higher speed than I thought possible. And I didn't scream like a little bitch either!

Jims5543

What rate springs are you using and what size tires? -2° front camber is telling me you are using either some really high profile tires or really soft springs.

Fluid Dynamics

They are dual rate eibachs that are about 80/160. They pretty much suck, but came with the car and are an improvement over the stockers, in only for the drop in ride height. I'd get the racing beat spring and sway bar package if I had five hundred bucks at my disposal.



My tires are 50 series BFG comp t/a's with a relatively soft sidewall. Once I get some real race rubber, I'm sure my setup will need to be adjusted.

Jims5543

Deal with the springs you have and save your money until you can afford a set of coil overs. I made the racing beat mistake myself. I ended up selling them at a loss 6 months later for a set of coil overs.

Fluid Dynamics

That's a really good idea. Lol. I'll remember that when I get $$ some day.

FCmaniac

I put the RB front sway bar in and the GXL rear bar. The car pushes too much. Do you think an LSD swap would take care of this? I'm talking about autocross. My problem is that I don't get out enough and each time I change or adjust something, I can't get enough time to tell if I need to change the part or change my driving style or what.

Fluid Dynamics

If your car is "pushing" it is understeering. LSDs increase understeer. Swapping in an LSD would make your car push more. If you want to run an LSD, the remedy I would choose would be to trade the RB front bar for someone's RB rear bar and get a GXL front bar instead of the thicker RB one (softer anti-sway bar in front and stiffer in back).



I think a lot of people swap in a thicker front anti-sway bar just because it's better than stock, but don't realize that without balanding it with a thicker rear bar too, it will cause understeer, and that is not good for being fast around curves.

FCmaniac

Yeah, I put in the RB front bar after reading peoples recommendations of making the car neutral... but for autocross, it feels worse. I'd like to upgrade to an RB rear or what you said, just try a GXL front. I noticed that running without any front upper strut tie bar, I get some of the turn in back as if its reducing the understeer. One more reason for not going with an RB rear bar was to try and keep the inside wheel planted for better traction since I have the open diff. I could be way off on that but I think the sway bar would affect that.