Your Sunred SR21 is an incredible racer.
I'm going to order another one.
My track is very twisty and the straights are fairly short.
I'd like the highest gear ratio I can fit on this car.
What pinion/spur gears would you recommend?
I'm using your D3 motor.
TSR has four basic gear ratios available but the use of the TSR-Ortmann Urethane based tires on the 1/32 scale chassis places limits on what can be used because of the smaller tire diameter.
The stock ratio uses a 14T pinion and a 45T spur gear. This provides a 3.21 ratio.
The largest spur gear that can reasonably fit is a 47T, using the 12T pinion. This provides a much shorter ratio of 3.91. Hopefully and using the torque of the TSR D3 motor, it should improve acceleration and braking, at the risk of becoming dizzy on a short course!