From memory the maximum cold pressure is 44psi. It's written on the sidewall. I set 40psi front and 38psi rear, though admittedly I haven't checked recently.

 

I was thinking of riding around 38-40 psi. I don't mind a harsher ride. Has anybody seem a better mpg as a result of firmer tires?

 

Your mileage will go up. The only worry you should be considering is don't go too high. I'ts not a matter of harsh ride, but if too high it might be likely to explode.

 

I filled up today and even though it is very hot outside and my tires might have been hot. I filled up to 36 psi. I figure when it is cooler I'll be riding at a good 33 or 34.

I've been getting 35-38 mpg avg since I got my car 7-13-07 on psi that was probably filled since it was done at the factory in Japan.