From another thread, moved here as more appropriate place for it and most is likely covered already in this one
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15" wheels have many benefits, lower weight being a top priority.
Lower weight improves acceleration, improves cornering grip by allowing the suspension to keep the contact patch on the ground better, improves braking, improves fuel economy and reduces wear and tare on the chassis. 15x8 wheels with 225 tires can weight as much as 10lbs per corner less than the stock setup, 40 pounds of unsrpung rotational mass is a huge savings.
17" wheels on this car with small fender area reduces tire width one can run, most wider tires are to tall and the ride is dramatically more harsh than on 15's.
15" wheels and tires cost less than comparable 17's as well.
I am a big fan of 16x8 wheels on this car as well, if not for the added gain of the 15's I would run 16's as they look perfect to me.
My wheel and tires, all wheels are 4x100 and roll formed which is the same as flow formed, etc, nearly as strong as forged wheels and nearly as low in weight but far less expensive.
*(4)15x9 Konig Helix 13.4lbs, $124 each, BFG 225/45/15 Rival S for street
*(6)15x9 Konig Helix 13.4lbs, $124 each, Toyo RA1 DOT race tires, 225/45/15 on all four corners
*(4)15x8 949 Racing 6UL,11.4lbs each, $159 each 205/50/15 Neo Gen AS tires, 31lbs per corner!
*(4)15x9 Konig Dial In 12.8 lbs, $119 each (selling)
*(4)17x7 Konig Feather, 16.8lbs well made cast, $99 each (selling)
Wheels sold:
(4)Stock wheels and tires, 293 miles on them
(4)15x9 Konig Dial In, one set left.
(4)16x8 Enkei FPR1, 14.8lbs, $219 each, returned to vendor to get the 6ul when I found a way to fit them over my BBK.