Which is lighter, small rims/tall tires or big rims/thin tires?

[Jason@SportsCar]

Originally Posted by slow.yaris

nope.

small rims/tall tires - lightest

15 inch rims start at 9 lbs. I haven't seen 17s under 17 lbs. The tire difference with the two is maybe 2-3 lbs.

That is a poor example, or you just have not looked hard enough. The weight difference is not nearly that extreme IF you get comparable wheels. Yes, good 15" wheels are 9lbs, but the cheap stuff is 12lbs or more. There are also 17" wheels that weigh 14lbs or less - hell the 18"s we raced on for the previous 5 seasons we 16lbs.

Surprisingly tire size does not change the weight nearly as much as wheels, the difference between a 15" and 17" tire may only be a 2lbs - this is using the same brand and same model of tire. As the diameter of the tire gets bigger, so does the hole in it, you will typically only see an increase in weight if the circumference or width of the tire is increased.

We tested this back to back on the track... A 5lb per corner weight increase (this was using identical size and offset wheels, both with the same exact tire, the only difference being a 5lb increase in wheel weight) varied between one and two tenths of a second slower per lap on a 45sec autocross course.

In the end smaller is lighter, but its not always the best performance package... For a street car, get what you like, and don't sweat a few pounds.