Another First Auto-X & Tire pres questions

[san rensho]

Originally Posted by jb92563

Thanks for the tips.

I guess I need more grip in the rear so lowering the pressure a couple PSI may help that.

Since the fronts are sticking well, my turn ins are very sure footed with the help of brake to load the front tires, but the rear tends to come unstuck as the direction change completes so perhaps I need to get on the gas sooner as well to load up the rears to keep them stuck down.

I think I'll start a notebook to track what I did and whether it improved things or not.

I'll drop the rears 1 psi to 35psi for next time out.

Next I need "Harry's Lap Timer" so I can video and analyze what I did that day.


I was hoping to get a lot more feedback but perhaps the racers are on other forums?
Is there a busier Racing tips forum somewhere or do the racers share no secrets in general?
Just trying to learn and am looking for more info on tuning tires.

If you are on the brakes as you turn (trail braking) then that explains the rear coming out. Trail braking does that, which is one way to get around understeer.

[stephen wilson]

I've only done one autocross, but noticed that the quick transitions of slaloms make a normally understeering car oversteer. Sort of like the "scandinavian flick" in rally racing.

[jb92563]

Originally Posted by san rensho

If you are on the brakes as you turn (trail braking) then that explains the rear coming out. Trail braking does that, which is one way to get around understeer.

I brake before any turning takes place like we were taught in the PDS except where I end up coming in too hot every now and then and I definitely know my mistake at that point and the consequences of breaking in any part of the curve.

I mostly noticed my rear tires loosing grip a bit in a big sweeping curve while accelerating.
It was throttle steering through most of that part and the instructor felt the tires weren't "locking up" as well as they could.
To make matters worse the track was banked AWAY from the inside of the turn.

He mentioned adjusting pressure but did not say which way before he had to jump in his own car to grid for his laps.