Will larger rims slow a car down?

[padam]

Just curious. We've only changed/tested wheel and tire changes. Not one or the other. We gained a tenth. But the front tire went from a narrow bias ply to a considerably wider steel belt. I would guess that the location of the weight matters considerably, and the change is probably not linear relative to distance from the centerline.

Years ago a friend was a distributor for aluminum driveshafts, and the claim was that they reduced ET by something like .200 seconds.
I was skeptical, something just didn’t seem right in my mind. I guess being that the drive shaft is trapped between the trans and rear end.

Maybe the same thing with rear wheels: they can’t rotate any faster than the tire which is fixed to the track surface.

 

[33 IMP]

Taller wheels increase rollout cutting your gear and your off the line speed. Lighter ( especially Rolling weight) is a good thing.

Taller front tires will increase rollout, and make a car APPEAR quicker, but make cutting a light against a pro tree much harder.

 

[R413]

Doug's example results are complicated buy the gear change. I don't have experience with a 9 second racecar, but usually going from 4.30 to 4.10 will slow the 60' time and the ET, and the lighter wheels will pick it up. But since it wasn't one thing at a time we don't know for sure.

Way to tell is put the other wheels and tires back on.

Compare an adult picking up 10 lbs which is easy, and a 5 year old will struggle to control it. The adult is overpowered and it won't be a challenge. Now the 5 year old is underpowered and it's noticeable.