Forgive my ingorance. I have no spare tire since my car (2005S) came with run flats. I now have non-run flats so I am looking for a donut or a regular tire in the event of a blow out.

 

If you keep the outside diameter of the 15" spare close to that of the 16", you should be fine.

 

a follow-up question:
will a 15" rim clear the standard S brakes (non-JCW)?

 

I think the spare on my 06 MC is a 15" but I could be wrong. Partsman is right though so long as its close it will be fine.....just dont leave it on there for an extended period as that is why its called a "spare"....not for extended use.

 

I know the stock 15" Holies will fit, other than that, don't know.

 

I run 15 inch wheels with my snows on a 2003 MCS. I've tried on 3 different sets that I have for my miata and they'll all fit .

 

If you have a flat on the front, you can always put the spare on the back and move a regular wheel to the front.

 

The standard 15" wheels will clear the S brakes on the non-R56 cars. Mine for example:


Like Partsman mentioned, the overall diameter of the tire is what needs to be close to stock, not the wheel diameter. A 15" wheel with 175/65/15 will have nearly the same overall diameter as a 16" wheel with 205/50/16.

 

A good rule to remember, if you have an odd sized wheel for a spare, is to put it on the rear for a FWD car

 

Will a 15" wheel fit our brakes? The answer is 'maybe'. It depends on the shape and offset of the wheel. As someone mentioned above, the 15" will fit more easily on the back wheels (smaller brakes), so if it won't fit the front when you have a front blow out, put the 15" on the back and move a good back wheel to the front.