Autocross vs. Track set-up advice
09-02-2008, 10:14 PM
#1
Three Wheelin'
Thread Starter
Autocross vs. Track set-up advice
I don't think I am going to get to race anymore this year. Our zone (Zone 1) has a big autocross coming up and I'm thinking of doing it in lieu of being totally dry for the balance of the year.
My car is a track car set up for PCA D stock. (2500 lbs, 23/31 t-bars, 31/27 SRP ARB's, 245/275x17 DOT-R's, custom shocks, Hawk race pads, and all the safety stuff). I'm sure this puts me in an ultra competitive class as far as autocross is concerned but really I'm just out there to have fun.
What changes should I make to a full track set-up to make it more autocross friendly? Also, I'm assuming I want a street pad for this right?
My car is a track car set up for PCA D stock. (2500 lbs, 23/31 t-bars, 31/27 SRP ARB's, 245/275x17 DOT-R's, custom shocks, Hawk race pads, and all the safety stuff). I'm sure this puts me in an ultra competitive class as far as autocross is concerned but really I'm just out there to have fun.
What changes should I make to a full track set-up to make it more autocross friendly? Also, I'm assuming I want a street pad for this right?
09-02-2008, 10:37 PM
#2
Burning Brakes
If you are using Hawk blacks, and even blues, they warm up relatively fast, but you may have to adjust your first hard braking point, so you may not need street pads. I would also recommend loosening the front A/R bar and stiffen the rear one to get more rapid rotation. Other than this, you may have higher rear tire pressures than you normally would at the track, may be as much as 2 or 3 psi and probably about 1 psi lower on the fronts, but it will depend on the overall feel; it probably will be a little trial and error first one or two runs.
09-03-2008, 09:32 AM
#3
What are your current alignment settings? There is a possibility you might want
more negative camber, maybe more toe-out in the front, and although I
definitely prefer a little toe-in in the rear, I know of a *good* GT3 autocrosser
who is liking a little toe-out in the rear!
more negative camber, maybe more toe-out in the front, and although I
definitely prefer a little toe-in in the rear, I know of a *good* GT3 autocrosser
who is liking a little toe-out in the rear!
09-03-2008, 09:37 AM
#4
Three Wheelin'
What are your current alignment settings? There is a possibility you might want
more negative camber, maybe more toe-out in the front, and although I
definitely prefer a little toe-in in the rear, I know of a *good* GT3 autocrosser
who is liking a little toe-out in the rear!
more negative camber, maybe more toe-out in the front, and although I
definitely prefer a little toe-in in the rear, I know of a *good* GT3 autocrosser
who is liking a little toe-out in the rear!
09-03-2008, 11:47 AM
#5
1) Add a lot of air to your tires - your tires won't get nearly as hot in an autox as they will at the track, so the difference between cold & hot pressures won't be nearly as much. I normally pick up about 10psi in the first session at the track, but only about 2-3 psi in the first session at an autox.
2) Adjust your setup to add more oversteer... if you think you've added too much, add a little more. You'll be the fastest when you have so much oversteer that you can't put the power down, and then back off just a little bit. This means more rear bar, less front bar, less toe in (even a little toe out), keep camber roughly the same.
3) Adjust your driving to add more oversteer - trail brake on corner entry a bit more than normal to get the car to rotate to the apex, then keep it from coming around with full power. While you don't want to "drift" the course, you do need to drive a little bit like a rally driver compared to what you do at the track. Smoothness still counts though - the quickest cars still will look the slowest.
2) Adjust your setup to add more oversteer... if you think you've added too much, add a little more. You'll be the fastest when you have so much oversteer that you can't put the power down, and then back off just a little bit. This means more rear bar, less front bar, less toe in (even a little toe out), keep camber roughly the same.
3) Adjust your driving to add more oversteer - trail brake on corner entry a bit more than normal to get the car to rotate to the apex, then keep it from coming around with full power. While you don't want to "drift" the course, you do need to drive a little bit like a rally driver compared to what you do at the track. Smoothness still counts though - the quickest cars still will look the slowest.
09-03-2008, 12:35 PM
#6
Three Wheelin'
Thread Starter
thanks guys.
sounds like i need to:
-dial in a 1/8" to a 1/4" of toe out
-set pressures about 2-3 psi below my normal hot pressures. front higher than normal
-soften the front bar
-stiffen the rear bar
my camber is already max'd up front and I don't want to mess with the rear alignment for this one event.
sounds like i need to:
-dial in a 1/8" to a 1/4" of toe out
-set pressures about 2-3 psi below my normal hot pressures. front higher than normal
-soften the front bar
-stiffen the rear bar
my camber is already max'd up front and I don't want to mess with the rear alignment for this one event.
