No problem, I was shocked to find such a low roll out but ended up with the fastest laps in the main so it can't be to far off. I too was shocked at the gearing on the brushless motors, it seems that the hottest modifieds are running what we use dto run with stock motors.

We typically talk rollout when asking about gearing for foam tired pan cars. I had 42mm tires, with a 48 pinion and a 76 spur. This equates to (76/48)*3.14159*42 which is 83mm of rollout. I am running a Speed Passion 1 cell 17.5 set at 20 degrees of timing. The current SP motor is the MMM and I would gear it the same with the same timing. I honestly thought I was closer to 90mm on rollout and will likely be trying it on Sunday, my first run with the car had the axle to tight on the bearings which caused heat. I geared down before finding the tight axle and never geared back up.