I'll be running V710's (275/40-17) in A/X this year and was wondering what a good starting point is for psi?

I think Kumho recommends 35psi and move up from there. 35 seems kind of low to me and was thinking of starting at 40 f/r.

I've also been running around an 8psi difference between my front and rear Dunlops (fronts higher), to balance the car... is it still necessary to continue running that much pressure differential?

 

I know Corvette drivers who run with 13 PSI in their 710s, so 35 is really quite high.

 

Wow, now that really seems low to me. Maybe they can run lower pressures because they have much wider tires??

What's the best way to determine pressures? Should I use a pyrometer and increase pressure until the tires heat up to optimum temps, or am I just trying to get an even temperature across the width of the tire?

 

Roll-over is probably the easiest (and cheapest) way.

If you have a contact pyrometer and can get accurate tire temps across the tire surface, you should be able to determine the correct pressure.

Another way is to use G loads -- the higher the load, the better the tire pressure matches your car and driving style.

However, you need to be a very consistent driver to make sure that you are getting good and consistent data.

 

I run 29PSI up front and 24PSI in rear. I set these based on roll-over.

 

36-37 up front

30-32 in the rear