Now it gets a bit strange-
so even with a heavy car, as long as the friction on the wheel is the same in both cases- they stop the same. This even infers that as long as the DFW was on the rail all the way down the track for both a heavy or light car- same effect. Now back to a front weighted car- it might need to be tuned a bit to roll the same as a rear weighted car- but the speed difference is totally within the range predicted by the slight height above the track difference calculation.
So when we tune and see a big difference in times, is it because when close to zero drift, the car can hit the track any number of times losing a lot of energy each time, and as we add drift we get it to roll completely snug all the way down the track. Now OVER steer will put the edge of the wheel in contact with the rail where it grinds as opposed to rolls on the bottom and the friction increases fast. The back wheels are canted where any touch at all grinds the wheel against the rail and that friction is way higher than rolling friction.
So to summarize- heavy car is faster we know- but the friction laws do not explain it and gravity does not explain it- Inertia of the car down the straight is not quite the effect- except more momentum does help against air friction. Is it all air friction? If we ran these cars in a vacuum would they come out equal?

so even with a heavy car, as long as the friction on the wheel is the same in both cases- they stop the same. This even infers that as long as the DFW was on the rail all the way down the track for both a heavy or light car- same effect. Now back to a front weighted car- it might need to be tuned a bit to roll the same as a rear weighted car- but the speed difference is totally within the range predicted by the slight height above the track difference calculation.
So when we tune and see a big difference in times, is it because when close to zero drift, the car can hit the track any number of times losing a lot of energy each time, and as we add drift we get it to roll completely snug all the way down the track. Now OVER steer will put the edge of the wheel in contact with the rail where it grinds as opposed to rolls on the bottom and the friction increases fast. The back wheels are canted where any touch at all grinds the wheel against the rail and that friction is way higher than rolling friction.
So to summarize- heavy car is faster we know- but the friction laws do not explain it and gravity does not explain it- Inertia of the car down the straight is not quite the effect- except more momentum does help against air friction. Is it all air friction? If we ran these cars in a vacuum would they come out equal?