A&Q about 350Z
Q:
Directional tires dissipate water better in one direction due to their design. That is why they have to spin the direction as indicated on the sidewall. If you could get a set of reat rims and tires that would not rub the inner fenders you could go with the same size all the way around. I have a 92 Corvette as well as the 03 350Z and that was the last year that the C4 Corvette had the same size tires all the way around and that allows you to rotate the tires from front to back. In 93 they went to bigger tires on the back so after 92 you could no longer rotate tires from front to back. I suppose on the 350Z the rear tires would be too big and would cause interference problems. You would probably have to limit the steering travel to keep from rubbing the tires. On my 86 Mustang GT the front tires rubbed from the factory and I ended up moving the K Member in to keep the tire from contacting it.
A:
see engine problem topic on why it is not wise to rotate your 350z tires if your 350z is equiped with bigger tires in the rear