[donee]

Hi All,

What am I missing? The experience in the Prius comunity is that the bigger section tires have worse mileage. Dramatically worse. For example, people who have put on 17's (225 section?) have a hard time toping 40 mpg as reported on Prius chat, in 2nd Gen Prius. Wheras people with the 185R15's easily top 50 mpg. Both the tires have about about the same diameter.

Also, a constant load rating tires that is bigger in diameter will have a smaller section (similar enclosed air volume). One would expect the larger diameter tire to have less rolling resistance due the smaller flexing.