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PCA Potomac is sponsoring a DE this coming weekend on the Shenandoah Circuit at Summit Point.

Is anyone else going?
 

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Yes, I'm planning on being there. 944T track car is OOC, so I'll be running my Boxster S (car #880) on the track for the first time.

:cheers:
 

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Hey, either of you guys have any recommendations for cold tire pressures for RA-1's? On my 944T I run the same size wheel and tire (255/40/17) on all four corners, and I start out about 29 or 30 psi cold and they usually settle in about 38 psi hot.

On the Boxster I'll be running 235/40/17 RA-1's in the front and 27540/17 in the back. I'm expecting the fronts will heat up more than the backs, so I'm wondering what numbers I should start with cold front and back. Any suggestions?

:cheers:
 

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Hey, either of you guys have any recommendations for cold tire pressures for RA-1's? On my 944T I run the same size wheel and tire (255/40/17) on all four corners, and I start out about 29 or 30 psi cold and they usually settle in about 38 psi hot.

On the Boxster I'll be running 235/40/17 RA-1's in the front and 27540/17 in the back. I'm expecting the fronts will heat up more than the backs, so I'm wondering what numbers I should start with cold front and back. Any suggestions?

:cheers:
Sorry, no experience with RA-1s.

I am running 245/40/18 275/40/18 NT01's. Rumored to be same compound by Toyo, FWIW. I found the Nitto's raised 10-12lbs cold/hot, in cool ambient conditions. I am interested to see the change with higher ambient. My target hot was 34F37R. I've know others that prefer 1-2 degree higher for a good balance of grip and longevity.
 

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Thanks! I was particularly interested in learning whether it's still best to have a pressure differential between the front and rear tires when hot - similar to what's called out for cold street tire settings. So based on your experience, I should target about a +3 psi differential going from front and back when hot. That does make sense considering I will be running 235 tires in the front and 275 in the rear - higher pressure in the rear should help reduce understeer, but I don't think I want to go beyond 40 psi hot in the back because that's when the RA-1's can really start getting greasy.

I think I'll start out about -8 psi in both front and back from stock settings, and then bleed air if required as the day heats up. And based on how the car handles tweak the front/rear settings as necessary to keep the handling neutral.

I look forward to seeing you guys there on Saturday!
 
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