So i have a 2010 prius III model my question is how much will 16 or 17 inch rims affect my normal MPG? does anyone know what the 38mm 40mm etc etc..is? and what it effects? i enjoy being able to make a full uturn on a small street... 205/55R-16 38gmp <---whatever that is will these fit ok? but as soon as i get free time i'll go to a tire place and ask..but wanted to get some input
There are a few factors to consider for mpg loss: weight of wheel and tire, aerodynamics of wheel, and the rolling resistance of the tire you choose. The 38 and 40 mm you are refering to is the offset of the wheel. Do a google search on offsets to learn more. You can even go to tire rack and read up more about wheels in general.
I posted a response to a similar question in this thread: http://priuschat.com/forums/gen-iii...ions/78557-will-wider-tires-decrease-mpg.html
According to declared fuel consumption numbers here in Europe based on EU driving standard cycle, the difference is 0.1L/100km (or about 1 MPG) more with 17" wrt 15" on all test cycles (city/suburban/combined). There is no reason why it should more than this, since test conditions are the same and the wheels are the only thing that change.
There are posters who've taken a bigger mpg hit than that with aftermarket wheels, even with lighter rims but which are less aerodynamic compared to stock 17".
