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Ok, I have a question. Anyone know a formula to convert tire size and mpg ratings. Here's where I am at:
Stock tire size and speedo calibration is 225/70-15.
Current Tire size is 235/75-15, calculating 14 (13.945) mpg. This was done over 3 tanks, miles driven divided by gallons in to full. Remained consistent within 1/10th MPG.
Question I am looking for is what would that be for true MPG, given the speedo calibration.
Using the calculator at http://www.1010tires.com/TireSizeCalculator.asp I found that your stock tire would use 759.1 revs/mile and the size you have now is 720.4 revs per mile.
I took 14 mpg and multiplied by (759.1/720.4) and it gives me 14.75 MPG.
That makes sense to me, as you are actually travelling further than your Odometer reads, due to your larger diameter.
Indeed, thats the direction I was going in. Was hoping it would be closer to 16. But I am in need of a new thermostat. So now I have somewhat of a baseline to see the difference in the engine temp vs. MPG.
Thanks for the link. I have been wondering if there was something like that around.