What Autocross tire pressure have you settled on

[Al.B]

I’ve been auto crossing a 21 Supra on rt660 (BS) since March this year which is 4 events so far and have settled early on 32/30. That’s based off previous experience with the rt660 on my previous Ax car a Vette which I ran at 30/28 and basically going as low as I could on the fronts before rolling over past the shoulder marks. Also the pressure above is the pressure I set right before a run which is easier to test and control, for me at least. I’m remembering a YouTube review that reported the rt660 likes a bit higher temps than the typical 200tw and I’m just checking to see what others are running to make sure I’m not running lower than ideal.

Sponsored

 

[underdonk]

What class do you run?

 

[Al.B]

Street

 

[FLtrackdays]

I’m running on Maxxis Victra RC-1 and like to start off with about 28-30psi. As the day/track starts to heat up, I like to keep the pressure betweet 34-36psi. The reason I check before and after are because the conditions can vary. Sometimes (especially on other brands) the pressure can creep up to 40psi when track temps and lap times go up.

 

[Rocksandblues]

I think you are pretty close. If you are reading the tire wear you should be able to get it dailed in. Depends on how hot the day and asphalt are and how long of runs.

If you want to get a really good time and tires be damned- start at 27 cold

 

[AdamP]

I've heard rumors of a limp mode to low tire psi any truth to this?

 

[underdonk]

Serious question. Besides the extremes, do you feel like you're dropping time with minor tire pressure adjustments in an autocross?

 

[romanLegion9574]

I've heard rumors of a limp mode to low tire psi any truth to this?

I haven't had limp mode but the car does constantly complain that the PSI is low. I've found that I've needed to run the manual reset since it doesn't go away after I refill the tires the next day.

 

[Evolution]

If its going to be a hot day out, I start with my psi at 26. Also on 660s. They get up to around 29 psi after a lap. That seems to be the sweet spot. If you do a tire reset with the psi low, the car doesnt complain about it much. Just shows the tire light. Dropping or raising the psi does make the car act different but its more like fine tuning then anything.

 

[razorlab]

I've heard rumors of a limp mode to low tire psi any truth to this?

No, it will just turn the traction control back on when you hit over 10mph. But if you turn it off again it will stay off until you park the car.

I believe it's around 25psi or so when it does that.

That is my life at track days after the lunch break every time. lol

 

[romanLegion9574]

I ran the PS4Ses between 26-30 PSI cold depending on outside temperature up here in the PNW. I aim for 34-35 PSI hot. Once I wear these down, I was thinking of going to RT660s -- what pressure recommendations do you guys have for those?

 

[AdamP]

Awesome. I plan on doing nasa on stock tires and wheels then progressively move to 275 squared.

 

[mdpalmer]

I ran the PS4Ses between 26-30 PSI cold depending on outside temperature up here in the PNW. I aim for 34-35 PSI hot. Once I wear these down, I was thinking of going to RT660s -- what pressure recommendations do you guys have for those?

I'm running Continental Extreme Contact Sport 02 street tires which apparently are very similar to PS4S. How'd 35psi hot feel?

Anyone else have recommendations? I haven't done autocross in years, have an event coming up. Not looking to be competitive, just looking to have some fun and improve my skills. Tire rack has some generic information, wondering if any Supra owners have some suggestions.

https://www.tirerack.com/upgrade-garage/what-tire-air-pressure-do-i-use-for-track-and-autocross

 

[FLtrackdays]

I'm running Continental Extreme Contact Sport 02 street tires which apparently are very similar to PS4S. How'd 35psi hot feel?

Anyone else have recommendations? I haven't done autocross in years, have an event coming up. Not looking to be competitive, just looking to have some fun and improve my skills. Tire rack has some generic information, wondering if any Supra owners have some suggestions.

https://www.tirerack.com/upgrade-garage/what-tire-air-pressure-do-i-use-for-track-and-autocross

Very cautious but good link. It recommends starting (pressure) points. If it’s cold out, you won’t need to adjust as much. If it’s already hot out (especially on the tarmac), then you’ll be bleeding those pressures down even quicker. That’s probably the biggest take home. Don’t set it and forget it. Buy a nice gauge with a bleeder valve

 

[tomfree]

I've heard rumors of a limp mode to low tire psi any truth to this?

Not on my '22. I've run as low as 27psi with the TPMS working, and I've done complete track events with the TPMS not working. Zero limp mode issues.

Sponsored