1. What is a Tire Size Speed Difference Calculator?

Definition: This calculator determines the speed difference (mph) when changing tire sizes, comparing the new speed to the original speed.

Purpose: It helps vehicle owners understand how tire size changes affect their speedometer readings and actual vehicle speed.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( Diff \) — Speed difference (mph)
• \( S_{new} \) — New speed with different tires (mph)
• \( S_{old} \) — Original speed with stock tires (mph)

Explanation: The simple subtraction shows how much faster or slower your vehicle is actually traveling compared to what the speedometer shows.

3. Importance of Speed Difference Calculation

Details: Understanding this difference is crucial for maintaining proper speed limits, avoiding tickets, and ensuring accurate odometer readings.

4. Using the Calculator

Tips: Enter both the new speed (with different tires) and original speed (with stock tires) in mph. Positive results mean you're going faster than indicated, negative means slower.

5. Frequently Asked Questions (FAQ)

Q1: Why does tire size affect speed?
A: Larger tires cover more ground per rotation, making the vehicle travel faster than the speedometer indicates, and vice versa for smaller tires.

Q2: How do I find my new speed after tire change?
A: Use our Tire Size Speed Calculator or measure actual speed with GPS compared to speedometer.

Q3: What's a significant speed difference?
A: Differences over 1-2 mph can affect speedometer accuracy significantly and may require recalibration.

Q4: Does this affect odometer readings?
A: Yes, tire size changes affect both speedometer and odometer accuracy proportionally.

Q5: How can I correct the speed difference?
A: Options include speedometer recalibration, using a correction module, or returning to stock tire size.