Track tire pressure - at start and finish of session

[rob76turbo]

Originally Posted by 944boy

Don't ever get them above 40psi, they will become grease. I would suggest starting at 35 cold (depending on outside temp) and measure them as soon as you get off the track. I would aim for ~38 hot and adjust based on feel.

Front and rear at the same pressure (38 lb)?

Thanks!!

[944boy]

Well I am used to running the same size tire all the way around. You might want a little more on a wider tire (rear) and less on the front. I would at least start out the same. If its pushing you can raise the rear a little or lower the front a hair or opposite for oversteer. Whenever you make adjustments, do it in one or two pound increments. Also its good to make note of the outside temp and pressures in a logbook. That way you get a feel for what is working and have to do less guessing in the future. The best way to tell what the best pressure is; is with a pyrometer, but correct readings are an art and that's only truly needed if your really serious and competitive. For most of us, 'feel' of the car, how much the tire is rolling over, and a working knowledge of how the tire behaves can get you quite far.

[Sboxin]

I agree with 944boy -- except front =33 and rear =35 cold temps.
The 2 pounds difference between Fr and RR helps with the Boxster balance.
And, try to keep that log of temps and pressures so you can set the pressures at off track hot temps.
The R888's take a couple of laps to heat up, but after that they do stick very well!!!
Keep an eye on your power steering; this can fail and blow PS fluid all over the engine and exhaust if the fluid temps get too high from the R888 tires (look at my previous posts from 2007).

Enjoy!

Ed

[rob76turbo]

Perfect. This seems like a good start. Besides running the 888's, I also plan to have Park Place Porsche (DFW, TX) do a 4-wheel alignment. They have set up a lot of Boxster's for the track and I trust Randal Johnson (parts manager and track guru) on his recommendations.

[rob76turbo]

Originally Posted by Sboxin

I agree with 944boy -- except front =33 and rear =35 cold temps.
The 2 pounds difference between Fr and RR helps with the Boxster balance.
And, try to keep that log of temps and pressures so you can set the pressures at off track hot temps.
The R888's take a couple of laps to heat up, but after that they do stick very well!!!
Keep an eye on your power steering; this can fail and blow PS fluid all over the engine and exhaust if the fluid temps get too high from the R888 tires (look at my previous posts from 2007).

Enjoy!

Ed

Great!! I will keep an eye on this! Since this will be my first event of the year AND the first one in the Boxster, I plan to keep a very close eye on everything!!