tire size
I just got back from tire rack anf they did a full anizalition of the front and back wheel wells and will be able to give you the maxium size tires you ncan use.
tire pressure
You can fool with the pressures but in the end you would be much better off with Michelin's Pilot Sport PS2 (front 265-30-19 rear 335-30-20), with the Good Years you spend a lot of time skating around the corners.
does anyone know if I can get 315/30/19 on the front and 335/30/20 on the back;we just came back from a week of racing and the stock GoodYears were pushing all over the track. Or what do you suggest?