I am running 18/7.5 rims with 225/40/18 pirelli pzero nero all around i have 'em at 34psi ...is this a good pressure or would anyone suggest somethng else? thanks

It's a good pressure. I use 40psi on the same set-up (225/40 on 18x7.5") because I want my rims and tires not to be screwed up easily when I go over a pothole.