Now for a tire question

[TFOGGER]

Yes, they'll work, as long as they're the same size on all 4 wheels. The 225/60s will end up being slightly shorter than the 215/70s, and if you put them only on the drive axle, you may have the ABS/Traction control/VSS computer freak out.

The numbers aren't exactly right, as there is some latitude in tire manufacture, but:

215/70/16 overall diameter 27.86 inches = 746.59 revs per mile

225/60/16 overall diameter 26.62 inches = 781.37 revs per mile

So, roughly a 5% difference in speedometer reading as well. (speedo will be optimistic about 3 mph at 60, in addition to any existing error).



I used to be a car tire salesman in a former life, doing mostly custom fitments, so this crap is still knocking around in the back of my skull.

[GilpinGuy]

This calculator has worked wonders for me over the years. This should answer a lot of your questions.

http://www.miata.net/garage/tirecalc.html

This is a handy tool - thanks!

Yes, they'll work, as long as they're the same size on all 4 wheels. The 225/60s will end up being slightly shorter than the 215/70s, and if you put them only on the drive axle, you may have the ABS/Traction control/VSS computer freak out.

The numbers aren't exactly right, as there is some latitude in tire manufacture, but:

215/70/16 overall diameter 27.86 inches = 746.59 revs per mile

225/60/16 overall diameter 26.62 inches = 781.37 revs per mile

So, roughly a 5% difference in speedometer reading as well. (speedo will be optimistic about 3 mph at 60, in addition to any existing error).

The tires (all 4) that I'll put on the new rims are the same, factory size as the tires that are on the car now, so looks like we're good to go.