07-26-2011, 02:36 AM
These are borrowed brains but I thought I would share them. Enter in your current tire size and then the tire size you wish to run and this calculator will show you the aspects of both and the plus or minus difference between the two. Even to correcting your actual speedometer reading.
http://www.tacomaworld.com/forum/tirecalc.php
http://www.tacomaworld.com/forum/tirecalc.php