I think i'm going to be taking my 05 RX8 out to a few autocrosses for the first time towards the end of june instead of driving the S. The car is completely stock right now with the factory 225 all around bridgestones. What is a good cold/hot tire pressure to shoot for, should the rears have more pressure than the front? I just want a good baseline to start with since i've never run the car and all my previous cars used a staggered tire setup.

 

Bone stock I was at 38F/35R.

 

Boy these OEM Dunlops are teh suck! at our low-grip local site I settled on 37 cold for the Fronts. I played w/ the Rears, anywhere from 35-41. for the sake of getting the outside rear tire to bite on corner exit, I think the lower Rear pressures will be my best compromise.

 

Those are the tire pressures once they are hot correct? Also do you have the dunlops or potenzas?

 

Don't get me wrong, they're probably a bit better than say, any of the All-Season tire options out there. But compared to the Falken Azenises or Hankook RS2s of the world, they're not on the top rung of street tire grip levels.
They're fine for everyday driving.

 

For Autocross, Hot and Cold pressures are the same. You bleed pressure off between runs. Main ideas on the bridgestones is to have enough air in the front to keep them from rolling over. Their are small triangles on the sidewall that indicate the maximum contact area, that shouldn't be exceeded.

On the rear use pressure for balance. Increasing above 35psi the rear will start getting loose, lower will tighten it up.

 

I ran oem michelin pilot sports at 42F 38-40R. Anything above 38 or so will be good enough to prevent rollover so it becomes personal preference after that. I like the rear to be able to dance around a bit and felt that the high pressures gave great feedback and grip.