Originally Posted by
clinttredway
I've been away from the hobby for quite awhile now and I can't remember what effect changing pinions does VS changing the spur.. meaning more top end or more torque.. etc.. any info is appreciated.
Changing the gear ratio, whether by changing pinion, spur, or both, affects the power range of the motor. Larger reductions (smaller pinion and/or larger spur) will give better initial acceleration but less top end. Smaller reductions give the opposite.
Using larger pinions and spurs without changing the ratio moves the motor forward in the pod, which moves the CG forward and reduces unsprung weight. That can be another tool for changing the car's handling.