Tire Pressures for AutoX
 

Going to run an AutoX this weekend, was wondering what tire pressures should be for Front/Rear, car is 2012 370z coupe with sports package

Thanks for any info.

what type of tires are you running? Stock?

Road racing i know you want them at around F/R 32/30 HOT but thats on slicks and road racing. someone else will chime in with a better idea for ya

This is a good question, I'm most interested in hearing thoughts on running stock tires with a nitrogen fill at stock pressure.

You'll hear some good rough guidelines, but the bottom line is you'll get the best exact reference by looking at your own tires after a run. I'm still new at this as well, but my understanding of the very basics is (someone please correct me if I've gotten something backwards):

1) Look at the edge of the wear pattern after a run. If it looks like on corners you're wearing on part of the tire that's past the edge (there's a marker on the tire for where the true edge is), you need to increase pressure to prevent the tire from rolling over so much. Similarly, if you seem to be not using enough of the edge, you can drop pressure a bit to gain more grip.

2) Check tire temperatures across the width (e.g. near each edge, and in the center). They make proper tire pyrometers for this that use a thumbtack-type sensor you stick into the rubber, but you can also use a regular infrared thermometer to roughly do the same thing. You want reasonably even temperatures across the surface. If the edges aren't as hot as the middle, drop pressure to flatten the tire out a bit more.

^yep. I like using chalk on the sidewall to check rollover as well.

Ballpark start at 38 or so psi and look at how far the tire rolls following every run. That should be a good close start! YMMV...

I'd suggest 40 ft, 34 rear. It worked for me on road courses. Stock tires, 19" sport package, stock suspension & alignment.

I've been running 42 all around. Stock tires sport package. That's what my coach suggested.

ended up running 40 front and 36 rear, we were in the middle of the group, not bad, it was more of a chance to see how the car did. My son and I both drove the car and he bested me by .146

How were your times compare to others at 42 all around.

I'm not good enough to claim time changes. My coach did drive my car and we stuck like glue around Pacific Raceways.

your temps, is that measured hot or cold? I'm going on my first track event in a month and would like to know... I'm running stock tires on sport package rims as well.

also, wstar, good tips on the infrared thermometer to check temps on the edges vs the middle, i'll have to bring mine along!

Probably the guys talking about high 30's to low 40's are talking about hot temps. Cold temps would be significantly lower, and are also less consistent to adjust by. You're better off making your adjustments right after you come off the track: check temps or chalk wear indicators, check pressure differentials, and even out the pressures while hot, dropping or adding a few PSI as necc to get the best use of the tire surface by temperature/chalk.

no, you set it before you go out

Can someone elibrate on what your looking for such as tire temps across the tire and using chalk methods?

^^^What I do :tup: usually at 40-42psi front and 36-38psi rear for me.

Also deals with the tire itself too, won't be the same for everyone.