I've put together a little spreadsheet to help me understand wheel fitment, and I thought it would be useful to other people too. Basically, given a wheel's width and offset, you can easily calculate the distance between the hub to the rim. It seems like good stuff to know, to better determine how well a particular wheel will fit.

Please note a couple caveats. First, the specs for some of these wheels might be off - I cannot attenst to the quality of my initial data sources. Second, tire width also has a lot to do with fitment, since that is ultimately what might or might not rub.

Oh, also - the CE28N is the only aftermarket wheel I have personal experience with. During an autocross with r-compount tires and stock suspension, I got a slight bit of rubbing in the front. And that's with only sticking out 0.7 inches further than the stock wheel.

Is this of use to anybody? Any does anybody know the offsets of the 17" MY04 wheel?

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Good info. What about 18's

 

The diameter of the rim doesn't have anything to do with how far the rim sticks out from the wheel hub, its only the rim width and offset that matters. The only impact wheel diameter on rubbing is the sizes of tires that are usable and how wide they are on 18" or whatever sized rims.

You can can calculate the above distance from hub of any wheel by the following formula:

D = W/2 - O/25.4 + S/25.4

D = distance from hub in inches
W = width of rim in inches
O = negative offset in millimeters
S = width of wheel spacers used in millimeters (0 if none used)

Compare your calculation to the OEM distance from hub to see how much farther the rims stick out. Now you can just go to your car and judge for yourself. This is a good way to estimate how close you are.

If you are close, rubbing depends on how "fat" the tire you choose for the rim and how much negative camber you have in your alignment. I do not recommend changing your alignment (unless you actually know what you are doing) just to fit wheels as it also changes your cars handling.

 

bigal1, Fongu is correct - wheel width has nothing to do with how far the tire might stick out. I have rim size listed because for situations liks the SSR GT1 - different diameter wheels have different widths and offsets.

Also, I only looked at 17 inch rims because those are the ones that really interest me. Fongu posted the formula I used in the spreedsheet. (Thanks, I had meant to do that and forgot about it.)