RE: transmision gear and spur gear questions
update;
I got a 70 spur gear and 18t. the 18t or 20t do not fit. so to answer the questions you cannot go higher tooth and higher spur, the reason. the 20t is bigg and the 70 spur is bug you need to hange the motor housing.
So I wen with my orginal 16tooth, and a 70 spur a fster off the line . So I might do a opposite put in a 66 spur and a 20 toot on the high motor to get a fasterr high gear.
1. bigger spur will give a faster off the line, and 1500 batts ipopp and flip the truck on start up.
can never trust a hobbie shop