18's are just fine for the 370 as long as the offset is low enough to clear the brake caliper. That's for all wheels though. The barrel of the wheel will clear the brakes.
As far as running a square set up (example: 18x9.5 all the way around) that can also be done with no problems. I'm not sure if the VDC will act up if you have the same size tires all around though. You may want to do some research on that.
__________________
2009 370z touring w/sports package
|