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So Dialed RC Setup App on the App StoreSo Dialed RC Setup App on the App Store

Gear Ratio Calculator

Use our gear ratio and rollout calculator to find the right pinion and spur for your car, whether it's Team Associated, Tamiya, Traxxas, or any other make, . Enter your car's internal drive ratio to see the final drive ratio (FDR), and see the percentage change in gearing you'll get from a new pinion and spur.

Gears & Ratios

Enter your gearing to see the how your ratio will change.
Ratio
1
1
Ratio change
0%
Internal ratio
(Optional)
FDR
1
1
Rear tire diameter (Optional, for rollout)
Rollout
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RC Gear Calculator Pro

Change Impact Chart

Click/tap the gears to see how new gears will affect your ratio:
Pinion
Spur
13
0%
74
0%
14
0%
75
0%
15
0%
76
0%
16
0%
77
0%
17
0%
78
0%
18
0%
79
0%
19
0%
80
0%
20
0%
81
0%
21
0%
82
0%

Negative changes indicate a steeper ratio: higher top speed, but more strain on the motor/engine. Positive changes give more acceleration and put less strain on the motor/engine.

5 Stars on the App Store

Ian C.
Something every racer should have
Cody B.
Helped me get a perfect top out speed and keep good temps.
William W.
This is app is a big hepl to me to actually know and see what my drag car is doing very useful app, highly recommend it to anyone who drag race.
Cole M.
Great little tool, get their other app to called "SO DIALED" its a lifesaver for tuning!
Heath M.
It has changed me as a human, made me care a little more about humanity and the fellow creatures on this Earth. It's also a great R/C gear calculator.