Quote:
Originally Posted by g21
i just watch a lot you Ring lap videos 
i have no idea why my door placard says 51 psi for my rear tires and 46 front
and i thought they tested my G21 on the Ring too
I'm guessing it's for fuel economy. M3 door placard says 32 psi and that's where i run my G21 (but I have special high volume RPF1 18" rims so even at 32 psi it has more air than other rims) |
Those are crazy high pressures, lower them and you will get better grip and a more comfortable ride. There will be a fuel economy penalty.