1. What is the MPH Calculation?

The MPH (miles per hour) calculation converts engine RPM (revolutions per minute) to vehicle speed using tire circumference and gear ratio. This formula is essential for automotive enthusiasts and mechanics to understand vehicle performance characteristics.

2. How Does the Calculator Work?

The calculator uses the MPH formula:

Where:

• \( RPM \) — Engine revolutions per minute
• \( Tire\_Circum \) — Tire circumference in inches
• \( GR \) — Gear ratio (unitless)
• 60 — Conversion factor for minutes to hours
• 5280 — Feet in a mile
• 12 — Inches in a foot

Explanation: The formula converts rotational speed to linear speed by accounting for tire size, gear reduction, and unit conversions.

3. Importance of MPH Calculation

Details: Accurate MPH calculation is crucial for vehicle tuning, gear ratio selection, performance analysis, and ensuring proper speedometer calibration.

4. Using the Calculator

Tips: Enter RPM as positive values, tire circumference in inches, and gear ratio as a positive number. All values must be valid and greater than zero.

5. Frequently Asked Questions (FAQ)

Q1: How do I measure tire circumference?
A: Measure the distance around the outside of the tire, or calculate using tire diameter: Circumference = π × Diameter.

Q2: What is gear ratio?
A: Gear ratio is the ratio of input speed to output speed in a transmission or differential system.

Q3: Why are there conversion factors in the formula?
A: The factors convert inches to miles (5280×12) and minutes to hours (60) to get the final result in miles per hour.

Q4: Can this formula be used for any vehicle?
A: Yes, the formula works for any wheeled vehicle as long as accurate measurements are provided.

Q5: How accurate is this calculation?
A: The calculation is mathematically precise, but actual vehicle speed may vary due to factors like tire slip, load, and transmission efficiency.