Weight vs Diameter of Tire??

[mcrews]

am not familiar w/ 4 bangers.
Had a V8 in the infiniti that loved 1800 rpms
have a V6 in the Kia Sportage that has no torgue curve so the larger tires helped.

Tire rack ships to a local installer so you have more choices than you think. That was how I got hooked on the Kuhmos. They were a great price (even w/ freight). THe recommended installer was great and I ended up buying 4 sets over 200k miles from him.

[kirkerik]

Peak torque for my motor appears to be around 2800 rpm. So i suppose with the slightly smaller tire my rpms will go up a bit with an improvement in torque, given im at 2200 rpm at 55 with these 235's.

Probably little difference though.

[kirkerik]

So iwill go with the lightest possible that fits my needs.

Thanks all!

[RedDevil]

The width of the track may have a bigger effect than the circumference. It is a 4.5% difference.
The wider tire will have higher air resistance and less grip in rain at highway speeds (as more water needs to be squirted further aside).

Another thing; the heavier tire may well be harder to flex, so it would have a higher rolling resistance.
I'd go for the narrow tire and pump it as hard as I dare.