1. What is a Tire Size Calculator MPH?

Definition: This calculator estimates vehicle speed in miles per hour based on engine RPM and tire diameter.

Purpose: It helps automotive professionals and enthusiasts determine speed at specific RPMs for different tire sizes.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( S \) — Speed (miles per hour)
• \( RPM \) — Engine revolutions per minute
• \( \pi \) — Mathematical constant (~3.14159)
• \( TD \) — Tire diameter (inches)
• 1056 — Conversion factor (combines unit conversions)

Explanation: The formula calculates how much distance the vehicle covers per minute based on tire circumference and RPM, then converts to miles per hour.

3. Importance of Tire Size Calculation

Details: Proper tire size calculations ensure accurate speedometer readings, proper gearing, and optimal vehicle performance.

4. Using the Calculator

Tips: Enter the engine RPM and tire diameter in inches. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: Where does the 1056 conversion factor come from?
A: It combines conversions from inches to miles (63360) and minutes to hours (60): 63360/60 = 1056.

Q2: How do I measure tire diameter?
A: Measure from ground to top of tire when properly inflated, or use manufacturer specifications.

Q3: Does this account for tire wear?
A: No, worn tires will have slightly smaller diameters, resulting in slightly lower actual speeds.

Q4: What about tire pressure effects?
A: Under-inflated tires have effectively smaller diameters, while over-inflated tires have slightly larger diameters.

Q5: How accurate is this calculation?
A: It provides theoretical speed. Actual speed may vary due to factors like tire slip, load, and road conditions.