Hey guys is it true that the size of the rims affects the mileage of the car? Don't wanna sound stupid, but if the wheels are bigger don't take up more gas which in turn, racks up the miles? I'm planning on getting 20". I am currently on 19". Will that make a significant difference?

 

Yes but you probably won't notice it too much coming from 19s to 20s. Reason: They are heavier. More weight = more gas used.

 

Regardless of the size of the wheel, if the overall circumference of the wheel and tire size is close to the OEM size (within a few %) and the weight is about the same it won't negatively affect your fuel mileage. All larger wheels are not necessarily heavier, many quality forged wheels weigh less in 20" than the OEM 19s (mine are). Cheaply made cast wheels will be heavier and affect fuel mileage a little bit.

 

Yep it's the weight of the wheel + tire (some tires are heavier than others) what matters. Typical 20" staggered set up is 245-35-20 and 275-30-20. The overall circumference of that set up is slightly smaller (.8%) than OEM.

 

Not like these things get great gas mileage even if you drive like my mom.....oh wait a minute.....my mom is a lead foot too.....never mind.

 

Not only the weight of the wheel but also the circumfrance.

All things being equal, a 20" wheel will give *slightly* better milage than a 19" wheel as with each rotation of the wheel the car will travel slightly further since a 20" wheel has a larger circumfrance.

Of course, this is dependant on all things being equal including wheel weight.

 

A 20" set up with 245-35 and 275-30 has a smaller circumference than stock 19's.

http://www.1010tires.com/TireSizeCal...paction=submit

 

Larger wheels are capable of both increasing and decreasing your fuel consumption. Moment of inertia and wind resistance for the wheel and tire combo make the biggest difference. That does assume you use the same tire on both the new ones and the old ones.

 

How about a set of these? What would they do to your mileage and laugh factor?

 

That's why I said "all things being equal". Meaning that if you have the same weight wheel, same treadwidth to sidewall profile, etc. Obviously if you start changing variables you can no longer do a direct comparison.