i sent this PM to another use when he asked me about 17's and 18's and if it was a big difference in both appearance and performance. here it is....
the inch between 17 and 18 is probably the biggest inch out there.
17"
pros: cheaper wheels, cheaper tires, maybe a better selection in general, and in price range. also in general would be lighter weight, BUT you can get super light 18's. also won't be so flashy, but i don't know if thats what you are going for.
cons: more tire needed to fill wheel well. everybody has them
18"
pros: really badass looking. fills out wheel wells better, though i'd still recommend sport springs/shocks for either wheel size
cons: more expensive wheels, more expensive tires, more money to get light weight wheels, but when you do, then ohhhh man, then you're rockin. lower-pro tires = easier to do damage on pot holes.
its a tough call, if i had the dough, i'd do two piece super light 18's on my car. that'd look slick with some good springs/shocks. but again, if you roast the tires (like we all love to do) you have to pay more to get tread back on the car.
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