4 replies to this topic

[GregHub]

Okay, so I know this site is Mazda RACERS not Autocrossers, but I'm thinking of running a few autocross events this year to gain a bit more seat time in my new (to me) NA and am wondering if anyone has advice on what tire pressures to run. (Couldn't find previous posts.)

 

I'm guessing set them at what you'd want for hot pressures on the track (~38 psi) since there won't be time for them to warm up, but I'm not sure if what's ideal for the track is the best for 45-60 second runs every 15-20 minutes on an all in second gear autocross course.

 

Suggestions? Thank you.

 

Greg

[William Bonsell]

Are they still running autox at the Pleasanton Fairgrounds? Did that in the 70's with SCCA. Any how, I did a ton of autox'ing before going w2w in 2010. You didn't say what tires you are using, but I'd target mid to high 30's and just adjust a bit if they get too hot. I personally think the car control skills developed autox'ing help on the race track. Just be careful of the early apex syndrome.

Have fun.

[GregHub]

Sorry to leave out the tire info. Hoosier SM 6s, must be two years old (from the previous previous owner!), one set with 3 heat cycles and one with 8. Gonna use them up on autocross, track days, and early races while I learn the car before I pop for a set of stickers. At least that's the plan right now.

[Mark McCallister]

You can find general auto-x tire info at miata.net and other places, but probably won't find much SM6 specific.  Depending on ambient temp and sun, I'd probably start at 36-37 and expect them to come up a couple pounds, and take pressures before and after runs - you'll figure it out quickly.  Unlike being on track, with auto-x there is no down-time for the tire to cool, so it will be heating up for the entire run.

[Matt Reynolds]

I would start higher and work your way down.  Down here are AutoX courses are pretty tight and I ran 40 on Falken Azenis.  If the courses are tight, I would be concerned with the tire rolling under.  Check the sidewalls after a run and make sure you aren't rolling the tire.