I'm fairly new to this site and I was wondering if anyone is or has done any road racing/high speed autocros w/TL-s. I have 07 TL-S and done some high speed auto cross and thinking of doing some more but thought maybe somebody may have some tips on tire pressure settings.

 

for auto-x, i believe i put 40 psi in the front and 35 in the rear

 

So, I ran my stock 3G TL in an autocross recently -- first time with a FWD car. I went with a group of highly-modified Mustangs (Saleens, Cobras, supercharged and with suspension mods, etc.), most cars in the auto-X were not stock and there were no car classes, so I couldn't compare times to any FWD sedans w/ any consistency-- no other TL, one TSX, one Mazda 6, a Corolla...

The 3G TL understeers a bit naturally, so I pushed the tire pressure higher in the back than stock-- 40F/40R (cold) on Bridgestone Potenza RE970 Pole Positions (all seasons)-- to see if I could dial out some of the understeer. It seems to have worked.
The car felt really predictable on the concrete aggregate surface: still a pusher, with lots of body roll but a constant set. I felt some oversteer coming out of a couple of faster turns, too. The rear tires didn't show much shoulder wear at all; the front tires showed a little shoulder wear. Tire temps increased 4 psi on the front, but only 2 psi at the rear during the auto-X.

Any suggestions or thoughts on varying the tire pressures?

 

Will where did you go? My friend goes to the El Toro airstrip and hes taking me most likely on the 16th/17th of June weekend. This will be my first time doing autocross.

 

Too high. Try 36-38 psi HOT.

 

Auto Club Speedway in Fontana, through Speed Ventures.
El Toro autocrosses are mostly through the SCCA, IIRC, so there are car classes.

I'm considering rejoining the SCCA for its autocrosses.
That'd bring my street tires down to the OEM recommended [cold] PSI.
I'll try that and lower pressures than the 40F/40R cold at the next one.

 

I recently registered with speed ventures and I am doing Big Willow on Junes 1st. How was the autocross experience at AAA speedway with speed ventures? Would you recommend it? How many runs did you get in?

 

It was enjoyable and pretty informal compared to SCCA auto-X-- no tech inspection, no class runs, no work requirement for drivers, etc. I do recommend it, although the SCCA probably has more old iron and collectible cars participating.
The auto-X course was in a parking lot at the Speedway, while other big $ cars were on the oval itself ($175 for the "Roval" through Speed Ventures). Somebody wrecked on the Roval that afternoon, but the auto-X cars were all intact.

I was late coming back from lunch and left @ 3:30 pm, so I only ran about 15 runs, when I probably could have run 25+ (people leave, so Speed Ventures combines run groups towards the end of the day). We had a very large turnout that day, so there were 4 groups of cars which were given 1/2 hour of runs per group on rotation through the day.
My buddy did 40-45 runs in February, when there was a smaller turnout and only 3 groups.

Have fun @ Willow and El Toro!

 

Thanks for the response. I haven't signed up for El Toro yet, I am thinking about doing AAA with speed ventures now after your review. My friend only got 4 runs in at El Toro last time. Big Willow should be a blast though I can't wait.

 

4 runs per event is normal for SCCA Solo II auto-X points events, and you also have to work on the course (watch & pick up cones) for another group of cars.

Speed Ventures' next event isn't until August, which is why I am considering running the SCCA Solo IIs in the OC in June and July.