what are you guys getting for mpg?

[stroker87]

Originally Posted by piecesparts

Remember the wheel and tire are rolling weight and so with that in mind, there is only a small portion of it that is actully suspended and adding weight to the vehicle. It is not the weight that you are dealing with as much as it is the circumference that you have to get the wheel to turn effectively to make it work.

if that was true why is it that with my 22" rims witch is just a touch smaller Overall Diameter then my stock 17" rims I loose 2.5mpg??

driving the same trip cruise set at the same speeds??? I run from Chicago IL. to Cleavland OH. on business a lot I have made the run many times on my stock rims and on my big rims with my stock rims I get about 65 mile more to a tank

Sorry for the hijack, every one

[piecesparts]

Originally Posted by stroker87

if that was true why is it that with my 22" rims witch is just a touch smaller Overall Diameter then my stock 17" rims I loose 2.5mpg??

driving the same trip cruise set at the same speeds??? I run from Chicago IL. to Cleavland OH. on business a lot I have made the run many times on my stock rims and on my big rims with my stock rims I get about 65 mile more to a tank

Sorry for the hijack, every one

What is your gear ratio, tranny type, and what are the two different tire sizes that you are running? If you put your engine at a point where it is now running at an RPM that is just out of the band on the opposite end, it works the other way.

[Bad70sbchevy]

Originally Posted by stroker87

if that was true why is it that with my 22" rims witch is just a touch smaller Overall Diameter then my stock 17" rims I loose 2.5mpg??

driving the same trip cruise set at the same speeds??? I run from Chicago IL. to Cleavland OH. on business a lot I have made the run many times on my stock rims and on my big rims with my stock rims I get about 65 mile more to a tank

Sorry for the hijack, every one

It's probably resulting from a higher rotating mass from the 22" wheels. It takes more power to turn a heavier tire than a lighter one. Either that or a smaller OD is causing the motor to turn more rpms at 65 which can also cause a dip in mpg depending on how much of a difference in OD.

[FMBL]

07 yukon 5.3 auto 3.42's with 305/45-22 seems to get 12.5-14.5 city, hwy or combined.

[swb85]

Even with identical overall tire diameters, heavier rims (ie, higher mass) will absolutely hurt fuel economy, along with acceleration and braking. Look up Newton's law of motion if you're having trouble wrapping your head around it.