RPM Calculator
Calculate engine RPM based on vehicle speed, transmission gear ratio, final drive ratio, and tire size. Perfect for gear selection and transmission tuning.
Step 1: Vehicle Details
Understanding Gear Ratios
The transmission gear ratio determines how many times the engine rotates for each wheel rotation. The final drive ratio is the gear reduction in the differential. Lower ratios provide better fuel economy at highway speeds, while higher ratios improve acceleration.
Step 2: Tire & Options
About RPM Calculation
Engine RPM is calculated using the formula: RPM = (Speed * Gear Ratio * Final Drive * 336) / Tire Diameter. This calculation helps determine optimal gear ratios for performance, fuel economy, or specific racing applications.
RPM Calculation Results
Engine RPM at Current Speed
Gear Ratio Comparison
| Gear | Ratio | RPM @ Current Speed | Speed @ Redline |
|---|
RPM Range Analysis
RPM Calculation Formula
RPM = (Speed × Transmission Ratio × Final Drive Ratio × 336) ÷ Tire Diameter
This formula calculates engine RPM based on vehicle speed and gear ratios. The constant 336 is derived from unit conversions (miles to inches and hours to minutes).
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