Inside
No car selected — showing a generic 5×5 grid with approximate values (0.5°/step).
A / FF mount
B / FR mount
A / FF mount
B / FR mount
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Save on tires, batteries, motors & hop-ups.
Free RC tools to dial in your car between rounds.
RC Gear Ratio Calculator
Pinion + spur + internal ratio → final drive ratio, rollout, and chart of nearby combos.
RC Speed Calculator
Motor Kv, battery voltage, gearing, and tire size → top speed of any electric RC car.
RC Pinion Recommender
What pinion should I run? Pick your car and motor; get a starting pinion from real race setups, with the range racers run.
RC Gear Ratio Chart Maker
Build a printable pinion/spur chart for any class: gear ratio (FDR) or rollout (mm). 1/10, 1/12 pan, 1/8 presets included.
RC Corner Weight Calculator
Enter per-wheel weights to compute cross weight and balance, critical for oval and on-road tuning.
RC Shock Oil Weight Converter
Convert wt ↔ cSt ↔ Mugen / Yokomo numbers, plus starting-point oil weights by class.
RC Shock Damping Calculator
Changing pistons or oil? See how much the damping actually moves, at roll, bump and jump speed, before you open a bottle.
RC Battery Runtime Calculator
How long will your LiPo last? Estimate runtime by class and driving style.
Mini-Z Wheel Offset Calculator
Fitting an AutoScale body to a Kyosho Mini-Z? Get the exact wheel offset for any width, plus a wheelbase & motor-mount reference.
Free app
Have this calculator handy at the track
Pit Calc Pro puts this pill insert geometry calculator — and 8 more tools — right on your phone, so you're never without it when you need it most.

