Greetings.

I generally don't mess wheel size changes, as messing with the ones the car was designed with can open large issues.

However, I just acquired a low milage excellently maintained 2011 G37 S that is fun as hXXX to drive, and fulfills my
continuing preference for expressing my shifty-ness. And, the prior owner installed Achilles 245/35 ZR 20's on the front,
and 275/30 ZR 20's on the back; mounted on AZAD rims.
The vehicle corners amazingly, and there is no interference.

QUESTION:
The owner's manual specifies 33 PSI.

With these tires/wheels,
what pressure should be run???

(I've searched here for the answer, but there are conflicting ideas: Either "the same", or "increase to 36 psi..")

 

There is no magic number. Start with 33 psi, monitor tire wear and adjust pressure up or down as needed.

 

Well, Thanks!

 

I run 245 and 275 at 36 psi. Even wearing and not too firm or soft on pilot sport as3+. Each tire will have different sidewall flex. I'd start at 38 and drive around and adjust