7speed wrote:Third (and correct me if I'm wrong), Doesn't that kill your performance? All that unsprung weight and inertia can not be good for acceleration, braking, suspension response, and who knows what else.
I always subscibed to the school of thought that the only purpose for bigger wheels was to house bigger brakes. This car already has 11" discs up front, so bigger brakes would be overkill (IMO), so I"ll only ever have 15" (maybe 16") wheels on mine...if it ever gets here.
Depends on the situation. Normally, stock wheels are very heavy, even stock alloy wheels. Plus sizing the wheels by one and using a relatively light weight wheel (I'm not saying go nuts and buy Rota Circuit 8's) will decrease the unsprung weight and rotational mass of the vehicle by making the wheels overall lighter.
Also, if you are attempting to improve handling by getting better rubber, you usually have a better selection of tires with a slightly larger wheel, which reduces the profile of the tire. Most sport tires are not available in a sidewall aspect of over 55. They generally run in the range of 40-55 (they are available in smaller aspect ratios, but then the ride gets stupidly harsh).
Biggest difference I noticed in a car I had owned was when I had my Saturn SC1... 175/70/14's were the stock tire, I went to a 205/55/15 afterwards. Accelerated more quickly, and the handling was such a night and day difference afterwards. I'd imagine you'd see the same kind of performance going to a comparable 16"... maybe a 205 or 215 width if it doesn't rub.
Plus, 16's are a lot cheaper than 17's. And I think you can buy a full set of 16's for what a single Dub would cost.