235-65-17
Not sure if stock tires for the 4x2 are the same as the 4x4, but if they are, stock tires are 245-70-17s. A 235-65-17 is about an inch smaller, and will make your speedo off by about 4.8%. In other words, when your speedo says you are going 60, you'll actually be doing just a tad over 57.
Source: http://www.miata.net/garage/tirecalc.html
Source: http://www.miata.net/garage/tirecalc.html
Last edited by jasonw; May 18, 2011 at 10:28 PM.



