I went from 18" to 19" wheels on my 350z - and they look MUCH BETTER. I know the actual difference in size isn't much, but it makes a BIG difference to how the car looks. The wheel arches get filled so much better. If 20" wheels handled ok I would even go as big as that, because I think 20's would look superb - but I worry that the handling might get too bad.
When I first went over to 19's I noticed that the handling didn't seem quite as good as the 18's, but you soon get used to it. I know I am talking about the 350z here, but I think it may be similar for the 370z.
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'03 Grey >>> '06 Black >>>'10 Silver >>> '16 Grey ^
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