Need tire pressure advice

[BigBlueDart]

I'm going to be doing my first autocross on Saturday. I was just hoping to get some advice regarding tire pressures. I'm not sure if tire and wheel size make a difference, but I've got 205/50-15 Nitto Neogens on 7.5" wide rims. Stock suspension, but the wheels do have a small offset at +32.

 

[deadlydave]

The pressures are going to depend on your tire. I just autocrossed my stock 2 with similar sized wheels/tires for the first time a week or two ago. I ran 37lbs in the front tires and 39 lbs in the back. 205-50-15 Dunlop Direzza DZ102's on 15x8, +38 offset wheels. It was probably about a pound too high, as turn in and rotation were pretty solid. Upon inspecting the tread/sidewall at the end of the event (i was primarily instructing others), I wasn't using all of the tread.

 

[BigBlueDart]

I'll start at 36 in front and 38 in back, then. I'll be sure to bring some chalk, too, and fine tune it as the day goes on. Thanks for the feedback!

 

[BigBlueDart]

Or not... the event is being rescheduled. (bang)

Why do all the autocross events have to be on Sunday?

 

[deadlydave]

Or not... the event is being rescheduled. (bang)
Why do all the autocross events have to be on Sunday?

Proof that all of us autocrossers are going to hell? (detect)

 

[Spinitsidewayz]

Proof that all of us autocrossers are going to hell? (detect)

I don't know about you, but i make regular sacrifices to the cone clipping gods

 

[jasyatz]

I don't know about you, but i make regular sacrifices to the cone clipping gods

This is funny; but true. Waterfest is this weekend at Raceway Park in Englishtown, NJ. Ill be instructing/hosting the Autocross school/event We just opened up the saturday autocross school to all makes and models and now they are calling for rain all weekend.

Any ideas /superstitions that have worked for you to keep the rain away?

If its raining, I try to change tires the day before ( in the rain) as kind of an FU to mother nature. it works more than 75% so far.

On topic though; Dunlops like higher pressures to keep the sidewall stiff. I'd start front 36/38 and rear in the 30-32 range. If the front feels sloppy or pushy, go up 2psi. if the feels good, but wheel spin is extreme, lower down to 32/34 in the front. There's no wrong answer to tire pressure. it's really what works for you and your car. That said, I had better grip in the Dunlop Z2s at 32 psi up front, but hated the feel and burned the outer shoulder off the fronts in 18 runs.

As the saying goes; Ask 5 autocrossers what pressure they'd run on your car, you'll get 20 different responses.

 

[deadlydave]

I don't know about you, but i make regular sacrifices to the cone clipping gods

3 Events in and I haven't hit a cone in my Subaru. Slid a student's STI through a couple, then off the pavement and into the grass. "Yea, so...you don't want to do that."