17" rims and fuel economy

[MadMax]

Originally Posted by thebarber

not really...its all about tire size

oem is 185-60-15

205-40-17 are within 1.23% of the oem rolling size

215-40-17 are within 0.125%

really, youre only going about 1% farther rather than 7%...

My Yaris has 215/45ZR17 tires on it, and stock tires are 175/65R14s.

Go to this web site and submit those two sizes in, and you will see that the stock tire has a circumference of 72.09 inches (1831mm) whereas the larger tire I am running has a circumference of 77.31 inches (1963.6mm). That's a diameter difference of 6.75%.

Do the math and you will see the tire travels a distance of an additional 5.22 inches per rotation over the stock tire.

As the odometer is set for the stock tire, you must add the addition of 7% (rounded up) to the odometer distance traveled.