Quote Originally Posted by ekim952522000 View Post
Excellent points.

Actually I think it shows that it's not linear. Since as the HP goes up the cars require a higher percentage of weight to be taken off in order to equalize the lap times. If it was linear then for example a 5% weight reduction would have worked for the all the HP levels which was not the case.
My formula was not based on weight, but on HP. Your data that I looked at was linear with HP, given a constant starting-point weight.

The reason I picked HP is that I was trying to be class-neutral. Everyone is saying that a 2500 lb ITR car needs a larger reduction than a 2500 lb ITA car. Using HP accomplishes that. Using weight would require a different formula for each class.