I went autocrossing today. I'm running street tires right now because I had to buy my books and wasn't able to get any a6s or v710s. So my street tires in the front were extremly wore so I changed then out for my other ones that came on the extra set of wheel I brought. So I ran douglous zr s in the front and some riken tire in the back. The first run was fun, I keep it in second the whole time and over steered alot and my rear seemed really loose and wants to kick out. The second run I lowered the pressure to 32 all the way around. (was at 35) that run I understeered alot and it wanted to push through the turn. Like I could go full lock and it still wanted to go stright. I swear I breaked before I came into the turn. I don't know if it's just these tires are super shitty. Third-fifth I raised the pressure back to 35 and it still understeered. The last race I down shifted back to first in 2 turns and basicly used the power to slide out the rear to make the turn.


What should I do? I got beat by 1.4 seconds by the only other guy in my class which is a fully pepped c4 corvette running a6's. I would really like to beat this guy and I think if I solved my understeered problem I would of been alot closer.

Ps- I haven't change my alimment yet. I'm going to this week.

 

I'll load up the videos of my runs in a min...
[media]http://www.youtube.com/watch?v=41jJXN8XdLM [/media]

 

These viedos arnt in order or anything. My times in order were..

1. 35.67
2. 35.181
3. 36.178
4. 35.510
5. 35.172
6. i didnt get it. i think it was like a 35.5xx

 

Get some decent street tires dunlop star specs and alignment then see where you are at.
The car is usually loose at the rear and when it pushes its probably you're going in too hard.
Its normal for it to push on tight corners try to ride the brake a bit into the corner to get it to turn.

 

[media]http://www.youtube.com/watch?v=Vcun87fXP4k [/media]
[media]http://www.youtube.com/watch?v=aylvVMbFZOQ [/media]

 

In car video is usually much more helpful.

You were pretty far off the cones in the turnaround (as far as I could see).

 

What should you do?

Keep running different brand and grip tires front and rear. You'll get the hang of it. Everyone on this forum does it and it's the only way to go fast.

You're a ****ing train wreck.

--kC

 

It sounds like your tire pressures are pretty low. The ideal pressures vary from tire to tire, but the general rule of thumb seems to be to go 5-10psi higher than you would run on the street. Granted, I don't autocross much on my street tires, but my Dunlop Star Specs seem to work best around 40 psi. You can adjust the balance of the car by staggering the pressures a bit (ie: 40 front/38 rear), but it won't likely result in better times.

99% of the time understeer is the result of driver error, you just have to figure out how much grip to expect the front and learn not to ask the car to turn more than it's able. Also keep in mind, that when the car starts to understeer, more steering input is only going to make things worse.

My advice is to get a set of decent street tires, don't worry too much about getting the pressures just right, and get as much practice as you can. An alignment will help too, but not as much as the tires and seat time. I ran my entire novice year on the OEM alignment and didn't get R-comps until the last event.

 

wow, that is the first s2000 video that I have watched where it exhibited such understeer put some decent street tires on it (hopefully the same brand/model front and rear), and get a bunch of seat time.

or say **** it and build the car up for STR

 

yea it would of been nice but i dont have a cam. this was taken from a crappy regular camra by my step dad.

yea the way it was set up is you have a extremly late apex but i couldnt get the car to turn lol

"What should you do?

Keep running different brand and grip tires front and rear. You'll get the hang of it. Everyone on this forum does it and it's the only way to go fast.

You're a ****ing train wreck.

--kC"

yea, i really need some tires. theses really sucked. what do you mean i'm a wreak?

"It sounds like your tire pressures are pretty low. The ideal pressures vary from tire to tire, but the general rule of thumb seems to be to go 5-10psi higher than you would run on the street. Granted, I don't autocross much on my street tires, but my Dunlop Star Specs seem to work best around 40 psi. You can adjust the balance of the car by staggering the pressures a bit (ie: 40 front/38 rear), but it won't likely result in better times.

99% of the time understeer is the result of driver error, you just have to figure out how much grip to expect the front and learn not to ask the car to turn more than it's able. Also keep in mind, that when the car starts to understeer, more steering input is only going to make things worse.

My advice is to get a set of decent street tires, don't worry too much about getting the pressures just right, and get as much practice as you can. An alignment will help too, but not as much as the tires and seat time. I ran my entire novice year on the OEM alignment and didn't get R-comps until the last event. "


the car seemed to turn in great the first time but it seemed like as soon at the tires got heat to them they no longer wanted to grip.