Here's one you may find usefull if you're planning to replace your stock rubber with something bigger (why would anyone want something smaller?...).


Simply insert the stock tire size, then put in the tire size of the rubber you're thinking of buying.


It'll show you the difference in size, plus the difference in rotations per mile, etc.


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


Chris in NC

Here's the coolest calculator I've found...

Calculator (http://www.1010tires.com/tiresizecalculator.asp?action=submit)Edited by: GMC-2002-Dmax

http://www.bncoffroad.com/ratio/


Here is a good one, Tire size axle ratio etc. etc.http://www.dieselplace.com/forum/smileys/Geek.gif

Both of those are great sites - I'm saving them for future reference.


Thanks.

If you ever need to do it on the fly, here is how it is calculated:


285/75/16 example


285 X .75 (aspect ratio times width) gives you the height of the sidewall rubber X 2 divide by 25.4 (centimeters per inch conversion) plus 16 (the wheel diameter) = total height. In this case 32.83 inches.


Steve