Thanks.

Looks like the best ratio you can do, with that 51 tooth spur, is a 4.64 (11/51) with that spur....unless the smaller pinion (from TH) would work without pinching the motor to the tranny. The 10T at TH would yield a 5.1. I was thinking of going to a minimum 5.0 (14/70) with the 32 tooth Traxxas spur....or maybe even a 6.0 (12/72) if I needed more torque.

Goal is to dupe the stock Titan power, but with more run time. Looking at a 3S Lipo and a Feigao 7XL.