1. What is the Gear Ratio Equation?

The gear ratio equation calculates the relationship between engine speed (RPM), tire diameter, and vehicle speed. It helps determine the optimal gear ratio for performance or fuel efficiency.

2. How Does the Calculator Work?

The calculator uses the gear ratio equation:

Where:

• \( RPM \) — Engine revolutions per minute
• \( Tire Diameter \) — Diameter of the tire in inches
• \( MPH \) — Miles per hour (vehicle speed)
• \( 336 \) — Constant to convert units

Explanation: The equation shows how engine speed, tire size, and vehicle speed relate to the overall gear ratio.

3. Importance of Gear Ratio Calculation

Details: Proper gear ratio selection affects acceleration, top speed, fuel economy, and engine longevity. It's crucial for performance tuning and vehicle modifications.

4. Using the Calculator

Tips: Enter RPM (engine speed), tire diameter in inches, and vehicle speed in MPH. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What's a typical gear ratio range?
A: Most street cars have final drive ratios between 2.5:1 and 4.5:1, depending on the vehicle's purpose.

Q2: How does tire size affect gear ratio?
A: Larger tires effectively increase the gear ratio (make it numerically lower), while smaller tires decrease it.

Q3: What's the 336 constant in the equation?
A: It's a conversion factor that accounts for units (miles, inches, hours, minutes) in the calculation.

Q4: Should I use loaded or unloaded tire diameter?
A: For most accuracy, use the loaded (weighted) tire diameter when the vehicle is at rest.

Q5: How does gear ratio affect performance?
A: Lower ratios (numerically higher) improve acceleration but reduce top speed, while higher ratios improve fuel economy at highway speeds.