As buickboy said stock 15" size is 195/60-15. If you run 17" most common size is 215/45-17. Revolutions per mile is affected by overall tire size so bigger tire = fewer revs per mile and could give better mpg. But on avg bigger rims means bigger tires of which both will typically be heavier which adds weight to the car. Means its takes more gas to move the heavy wheel/tire combo. Also tread compound can affect mpg slightly. Stickier tires offer more rolling resistance compared to a harder compound tire and thus reduce mpg. If you want more mpg get a lighter wheel/tire setup with a beneficial rev per mile diameter. I run a 215/45-17 with a 17x7.5 rim and my setup is about 4lbs lighter overall than the stock 195/60-15 setup that came with car. If I could afford more expense 17" wheels I could lighten by a 3-4 more pounds.
Hatch Nation #9
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