[Prop1]

So many have asked about what effect a size change can make it's time to post a permanent sticky with the link.

http://www.wedgeracing.com/tire_size_comparator.htm

This is a new calculator. The old Miata site calculator no longer works. On this one, you just slide the bars for the associated size parameters for each tire.

EDIT: The Miata calculator is back: http://www.miata.net/garage/tirecalc.html

 

[Aleks]

Specifying Aftermarket Wheels

Diameter calculators have different formats. This One shows you theoretical equivalent diameters using different wheel sizes.

These are the specifications for the Calibers stock 17 alloys

Width & Rim 6.5J
Studs 5
Stud Pattern 5/114.3 4.5"
Horizontal Positive Offset 40-45mm
Hub diameter 67.1mm
lugs 12mm X 1.5 thread