1. What is Tire Revolution Per Mile?

The tire revolution per mile measures how many times a tire rotates to cover one mile. This value is important for speedometer calibration, gear ratio calculations, and vehicle performance tuning.

2. How Does the Calculator Work?

The calculator uses the simple formula:

Where:

• \( Revs \) — Revolutions per mile
• \( Height \) — Tire height in inches (from ground to top of tire)
• 20168 — Constant representing inches in a mile (5280 feet × 12 inches) divided by π (3.1416)

Explanation: The formula calculates how many rotations are needed for the tire's circumference to cover one mile.

3. Importance of Tire Revolution Calculation

Details: Accurate revolution calculation is crucial for proper speedometer calibration, fuel economy calculations, and when changing tire sizes.

4. Using the Calculator

Tips: Measure your tire's height in inches from the ground to the top of the tire (while loaded). Enter this value to get revolutions per mile.

5. Frequently Asked Questions (FAQ)

Q1: Why is tire height important?
A: Taller tires rotate fewer times per mile than shorter tires, affecting speedometer readings and vehicle performance.

Q2: How do I measure tire height accurately?
A: Measure from the ground to the top of the tire with the vehicle's normal load and proper inflation.

Q3: Does tire wear affect revolutions?
A: Yes, as tires wear down, their height decreases slightly, increasing revolutions per mile.

Q4: What's a typical value for passenger cars?
A: Most passenger car tires have between 700-900 revolutions per mile.

Q5: How does this affect speedometer accuracy?
A: Changing tire size without recalibrating can cause speedometer errors up to 10% or more.