1. What is Speed From RPM And Wheel Size Calculator?

Definition: This calculator estimates the speed in miles per hour based on the RPM (revolutions per minute) and wheel size in inches.

Purpose: It helps automotive enthusiasts, engineers, and mechanics determine vehicle speed when they know the RPM and wheel dimensions.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( S \) — Speed (miles per hour)
• \( RPM \) — Revolutions per minute
• \( WS \) — Wheel size (inches)
• \( 1056 \) — Conversion factor (combines inch-to-mile and minute-to-hour conversions)

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

3. Importance of Speed Calculation

Details: Accurate speed calculation is essential for gear ratio selection, performance tuning, and verifying speedometer accuracy.

4. Using the Calculator

Tips: Enter the RPM and wheel diameter in inches. The wheel size should be the overall diameter including the tire. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: Why is 1056 the conversion factor?
A: It combines 12 (inches to feet), 5280 (feet to miles), and 60 (minutes to hours): (12 × 5280) / 60 = 1056.

Q2: Does this work for any vehicle?
A: Yes, as long as you have accurate RPM and wheel size measurements.

Q3: Should I use wheel diameter or radius?
A: Use the overall wheel diameter including the tire (not just the rim).

Q4: How accurate is this calculation?
A: It's theoretically accurate, but real-world factors like tire flex and slip can cause minor variations.

Q5: Can I use this for metric units?
A: This version uses imperial units. For metric (km/h), the formula would be different.