I thought I made that clear in my question - explaining the speedo settings, however, if the speedo is not corrected it should show that you are getting less mileage by about 3%, I wanted to know if anyone has reset their speedo, and checked their mileage? also, the width (friction) plays a roll - not here since the width is the same, but then there is wind resistance raising the car allows more drag from various areas on the car. I was wondering if that was anything noticeable or not. do you pick-up that mile per gallon, or does it stay the same? just curious. thanks for the reply!