Mellonpopr said:
I'm cursious.. I typically don't do any roll racing but hear me out on this:
two identical cars, one weighs 4000lbs, the other 2800lbs, they both have the same horsepower at the wheels and kick it down at the same time going from 50 to 150. How much difference is that weight really going to make?
some speculat that because it's going from a roll it's all but a non issue. I find that hard to believe.. my car feels way faster when I drop off the passengers and when I pick up a 200lb passenger it feels like a turd again.
think about the equation F=ma where F = force, m = mass, and a = acceleration. Now re-arrange it to make a=f/m. To increase acceleration (when you start from a roll, a=0) in a situation where Force is fixed (i.e. your engine output), you have to decrease weight...
So yes, weight definitely does have an effect even in roll-on racing, but the effects are not as obvious as speeds get higher since at those speeds, aerodynamic drag, gearing and the powerband of the car play a bigger roll.
Look at the Lotus Elise and Exige. Quick cars espcially when you consider that they only have 190HP at the crank, yet they are able to pull 100_mph traps... How? weight... At elevated speeds though (i.e. above 100mph), they struggle because weight isn't as big a factor at those speeds as drag, gearing and whp).