1. What is the RPM to MPH Formula?

The RPM to MPH formula calculates vehicle speed in miles per hour based on engine RPM, tire circumference, and gear ratio. It provides an accurate assessment of speed for various automotive applications.

2. How Does the Calculator Work?

The calculator uses the RPM to MPH formula:

Where:

• \( S \) — Speed (mph)
• \( RPM \) — Revolutions per minute
• \( C \) — Tire circumference (inches)
• \( GR \) — Gear ratio

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

3. Importance of RPM to MPH Calculation

Details: Accurate speed calculation is crucial for vehicle performance analysis, gear ratio selection, and speed optimization in automotive engineering.

4. Using the Calculator

Tips: Enter RPM in revolutions per minute, circumference in inches, and gear ratio. All values must be valid (greater than 0).

5. Frequently Asked Questions (FAQ)

Q1: Why use 336 in the formula?
A: The constant 336 converts inches per minute to miles per hour (63360 inches per mile / 60 minutes per hour = 1056, then adjusted for formula specifics).

Q2: How do I measure tire circumference?
A: Measure the distance around the outside of the tire, or calculate from tire size using: circumference = π × diameter.

Q3: What is a typical gear ratio range?
A: Gear ratios typically range from 2.5:1 to 4.5:1 for most passenger vehicles, but can vary significantly based on vehicle type and purpose.

Q4: Are there limitations to this calculation?
A: This calculation assumes no tire slip, consistent gear engagement, and ideal conditions. Actual speed may vary due to various factors.

Q5: Can this be used for different vehicle types?
A: Yes, the formula works for any wheeled vehicle as long as accurate measurements for RPM, circumference, and gear ratio are provided.