1. What is a Wheel RPM To MPH Calculator?

Definition: This calculator converts wheel rotations per minute (RPM) to miles per hour (mph) based on tire diameter.

Purpose: It helps automotive enthusiasts, engineers, and mechanics determine vehicle speed from wheel rotation measurements.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( S \) — Speed (miles per hour)
• \( WRPM \) — Wheel rotations per minute
• \( TD \) — Tire diameter (inches)
• \( \pi \) — Pi (approximately 3.14159)
• 1056 — Conversion factor (12 inches/foot × 5280 feet/mile ÷ 60 minutes/hour)

Explanation: The formula calculates the distance traveled per minute (circumference × RPM) and converts it to miles per hour.

3. Importance of RPM to Speed Conversion

Details: Understanding the relationship between wheel RPM and speed is crucial for gear ratio selection, speedometer calibration, and performance tuning.

4. Using the Calculator

Tips: Enter the wheel RPM and tire diameter in inches. For accurate results, measure the actual loaded tire diameter rather than using the nominal size.

5. Frequently Asked Questions (FAQ)

Q1: How do I measure my tire diameter?
A: Measure from the ground to the center of the wheel and multiply by 2, or mark the tire, roll one revolution, and measure the distance traveled divided by π.

Q2: Why is the conversion factor 1056?
A: It converts inches per minute to miles per hour (12 in/ft × 5280 ft/mi ÷ 60 min/hr = 1056).

Q3: Does this account for tire slip or deformation?
A: No, this calculates theoretical speed. Actual speed may vary due to tire slip, wear, or deformation under load.

Q4: Can I use this for different wheel sizes?
A: Yes, simply input the correct tire diameter for each wheel configuration.

Q5: How accurate is this calculation?
A: It's mathematically precise for the inputs given, but real-world factors like tire pressure and wear can affect actual speed.