Not entirely. There are two factors to consider. Rolling diameter
(determined by the tire) and weight.

The weight matters because it takes more energy (read power) to spin a
heavier wheel/tire than a lighter wheel/tire. AND, WHERE that weight is
distributed makes a difference. Weight at the outer circumference takes
more energy to spin  (or stop) than weight concentrated at the hub.

When you go to a larger wheel you usually are adding additional weight
to the wheel/tire, but you are also changing the weight distribution,
usually by moving more of the weight away from the inner hub.

This all affects acceleration times. A longer circumference is harder
to spin, and a heavier circumference (even at the same size) is harder
to spin.

I certainly noticed it going from steel 14" wheels (205/70R14 tires) to
alloy 15" wheels (215/75R15 tires).

On Thursday, April 17, 2003, at 08:48  AM, John Rodgers wrote:

> I haven't actually driven on any 15 inch rims yet, but all my reading
> on
> the subject indicates little significant change. It't going to depend
> largely on the 15 inch tire actually selected.