Here you can find RC car Pinion and Spur gears, sorted by gear pitch and manufacturer.
To change gear ratio on your RC car, you need to change the pinion gear, spur gear, or both. The gear ratio might need to be adjusted depending on the motor/engine you’re running, or if there is differences in size between different tyres you’re changing between, but most often changing gear ratio is used to tune the car for the conditions or track that you are running on.
Please refer your car manual for correct gear pitch and size. Note the shaft diameter, too!
From EuroRC you find pinion and spur gears in a variety of types, such as 48P, 64P, 32P, Mod 0,6 (Tamiya), and Mod 1.