Postby hks_kansei » Thu Mar 13, 2014 3:31 pm
The main clearance issues that crop up are diameter, and spoke clearance.
Diameter is easy to measure, spoke clearance is a bit harder, especially since it can change a bit on MX5s, and it differs on every wheel.
Unfortunately there's not an easy way to test it without a trial fit.
Your best bet (without going over there) is to get 2 good straight rulers.
Lay one flat on the wheel hub, then measure how far above it the caliper sits (above meaning towards the outer edge of the car)
Get the wheel seller to do the same (but measuring from the mounting face to the inside of the spokes)
It will give you an idea of how close it is, but still won't be 100% (since the back of spokes are often curved, and there's no guarantee of correct measurement on the sellers behalf)
If they do clip the calipers, usually a small wheel spacer will correct it, but it's up to you to do the research and decide if you're willing to use spacers.
edit:
when you measure the caliper clearance, remember to add some leeway, MX5s use sliding calipers, so they can stick out further with brand new pads and rotors, and sit further in with worn pads/rotors.
1999 Mazda MX5 - 1989 Honda CT110 (for sale) - 1994 Mazda 626 wagon (GF's)