ive read that i will get better mpg when driving in town with lighter wheels. ive also read that i will get worse mpg on the highway. any truth to this?

 

It won't make that much of a difference really. But yes, theoretically that would be true.

In the city, you've got a lot of acceleration and deceleration...which heavier wheels require more power to do. On the highway....I'm going to say you'd have more of a completely negligible effect....since you're not changing speed much the momentum of the wheels will help you stay at speed...but you'll have to use power to get to that speed, so it shouldn't make any difference.

My 2 cents..

 

It realy just comes down to rotational mass. The lighter the better. It justs takes less power for the motor to spin a lighter wheel/tire combo.

 

By the way, you'll notice it looks like I said you're right, then explained why you werent', haha. Just to clarify...You're right about city, but highway I don't think rim weight has any real effect on.

 

it would have a miniscule effect in the same way that a 50 pound sack of rocks in your trunk would.

on the highway, by far the largest force acting against the car is wind resistance. highway mileage is not affected much by vehicle weight.

 

yep, exactly. On the highway, you're not really fighting against the vehicle's weight, since you're keeping the car at steady state. On a basic level, you're just fighting the wind to keep that steady state. So that, with what I said up there (which is related but not the same), the wheels won't make a difference.


[Modified by IntegraR0064, 10:23 PM 5/27/2002]