Originally Posted by edd5
If you are looking at the EVIC MPG you need to be aware that it is calibrated for your stock tire size. Going to a larger diameter tire you will actually be going a bit further with each revolution (your speedo will be off a bit too) but your EVIC doesn't know this. If your stock tires were the 33's when your speedo reads 70 your are really doing 74. In a nutshell, you are going further than your odometer says you are. You do lose a little mileage due to the tires being heavier (weight penalty) but it isn't that much. Try doing a manual calculation correcting for the size difference. Your ECM can only be programmed for up to a 33" tire so no help from the dealer on this. You could add an aftermarket box (like a Hypertech) to correct but it really isn't worth it.
Sooo true try comparing gps miles with your odometer then refigure your gas mileage with the actual gps miles. How about some pics with them bad boys on?
"Most folks are as happy as they make up their minds to be". Abraham Lincoln.
Last edited by son-of-a; 07-19-2012 at 08:19 PM.
Reason: add a question