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Gear Ratio Calculator

Calculate your speed at any RPM for T5, T56, and custom transmissions. Enter your axle ratio and tire size to see real-world speeds in each gear, plus shift points for optimal acceleration.

Note: Always verify calculations independently before purchasing parts. Results are estimates and may vary based on actual tire dimensions, manufacturing tolerances, and wear.

Transmission
1: 3.352: 1.933: 1.294: 15: 0.68
Tire Size
/
R

Calculated Diameter: 25.68"

Performance at 3,000 RPM
03672108144180
48mph
Speedometer
0246810
3x1000
Tachometer

Engine RPM

Shift Point RPM

Speed in Each Gear at 3,000 RPM

GearRatioSpeed (mph)Shift @ 5,500
13.3518.3 mph33.6 mph
21.9331.8 mph58.4 mph
31.2947.6 mph87.3 mph
41.0061.4 mph112.7 mph
50.6890.4 mph

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