Ah. Thanks for clearing that up.

Realistically it depends on the motorsport. IN most you want the llightest car you can find. 1) you will have better traction over a car that has the same width tire, since it can use the tire more, 2) lighter car will accelerate quicker, 3) lighter car will corner better, 4) lighter car will also brake better, 5) and a lighter car will have less problems because it has less weight to pull around.