I'm running my first autocross in a long time this coming Saturday in Santa Fe...first time in this MINI...wondering where I should start for tire pressures?

The tires are the Continental 175/65/15's.

Thanks...

 

I'm also doing my first autox with the 15" Contis this weekend. From what I've read about the MINIs and learned over the years:

At least 38 (high speed reommendation on the door sill) and no more than 51 (maximum pressure printed on the sidewall). More in the rear than the front to reduce corner exit understeer. I'm guessing 42/48 as a starting point and letting air out to adjust rotation and tire roll over as measured by chalk on the tread.

 

I ran 45 psi on the front, and left the rears at 51...I forgot chalk, and no one I could find had any, so I wasn't able to mark the tires...but after about 3 runs, I could see that wear marks were coming up the sidewall maybe 1/2 to 3/4 inch...so next time, I'm going to run 47-48psi.

Ran pretty good...won the novice class (about 10 entries), and took 2nd out of 7 cars in the HS class...a VW Golf TDI with some r-compound tires, and a much more experienced driver, and maybe another mod or two (sway bar...not sure), beat me by about 1.5 seconds.

It seemed to me that leaving DSC ON worked a little bit better for me, though we are talking less than 1/2 a second, and most or all of that difference could be explained away by my steep learning curve, or that I just happened to have a better run with DSC ON (for OTHER reasons than DCS), than when it was off.

Actually, it was my 3rd run that I turned DSC OFF, and that was my fastest run up to that point.

Anyway, lots of fun.

 

I ended up at 48/49 with slight oversteer. I have the sport suspension. My fronts were still rolling over right to the very limit of the tread shoulder on concrete. I ran with DSC and DTC off. I think they prevent one's learning to drive properly.

The car provided great feedback and is easy to correct with throttle, steering, or brakes. It dances really well when you get the line, speed, and inputs correct. I'm going to put 16" wheels and Dunlop Star Specs on it.

We use drywall to draw boxes around the cones here. That is what I chalk the tires with.

 

I don't have the sport suspension.

So you had oversteer? Wow...I had understeer...are you running stock alignment?

The chalk...right...actually, someone mentioned that to me right before my last run...not enough time to chalk the tires.

 

Yes the oversteer was quite pronounced when I started off with 6 psi higher in the rear. I still had some with only 1 psi difference. I could easily induce exit understeer if I overdrove the corner, but it was easy to back off without losing momentum.

I haven't done an alignment or anything else yet.

 

Wow, I didn't realize the new cars were coming from the factory with such narrow tires.

I've got Dunlop Z1 Star Special 205-50/R15s and the increase in grip was awesome. Their lasting pretty well too, for what they are. I would have gone to 215 if those tires came in that size for 15s. But oh well, next time.

 

Thanks...that's good info on those 205's...whenever my current st of tires wears out, I'll make the switch, unless I can afford a whole new set of wheels/tires before then.