Are you sure the B4 and the T4 have different final gear ratios? I always thought the trannsmissions were the same. The other thing that throws the gears off is the tire size, which I mentioned earlier.
I should be handed a penalty for gearing anyway, since where I race, we run Monster Stocks and P2K2's with 32/84 on either foams tires, or 2.2" rubbers. The Pro-Stock Stampede class isn't an easy class. I run a Bandit
, and some rin Rustlers. It's all about raw speed, at any cost. The motors are hot off the track, but we take good care of them and rebuild after every couple of runs. The brushes usually last, but the comms get pretty ugly sometimes. It's not easy being a stock motor pushing a Traxxas "sled" 35MPH.