Stock is 18x7? Considering that the minimum wheel width for a 255/35-18 is 8.5 inches, you might want to think about it a bit more before going that wide... Since the sidewall is so short already, you're not going to have that many options for the stock wheel unless you go quite a bit taller. You'll pinch the sidewalls too much on a significantly wider tire. 225/45-18 is as far as I'd personally want to go- this is assuming I'm right on the stock 18x7 wheel size.