1. What is Tire Height?

Tire height is the total diameter of a tire when mounted and inflated, measured from the bottom of the tire to the top through the exact center. It's a crucial measurement for vehicle fitment and performance.

2. How Does the Calculator Work?

The calculator uses the tire height formula:

Where:

• \( \text{sidewall} \) — Tire width in millimeters
• \( \text{aspect ratio} \) — Sidewall height as percentage of width
• \( \text{rim diameter} \) — Wheel diameter in inches

Explanation: The formula calculates the total diameter by adding the rim diameter to twice the sidewall height (converted from mm to inches).

3. Importance of Tire Height

Details: Correct tire height is essential for proper speedometer accuracy, vehicle clearance, suspension geometry, and overall performance. Significant changes can affect gearing and fuel economy.

4. Using the Calculator

Tips: Enter the tire width in mm (first number in tire size), aspect ratio (second number), and rim diameter in inches (third number). Example: For a 235/40R18 tire, enter 235, 40, and 18.

5. Frequently Asked Questions (FAQ)

Q1: Why is tire height important?
A: It affects speedometer accuracy, gear ratios, clearance, and overall vehicle dynamics. Incorrect height can cause rubbing or performance issues.

Q2: How much can I change my tire height?
A: Generally, staying within ±3% of original height is recommended to maintain proper vehicle function.

Q3: What's the difference between tire height and diameter?
A: They refer to the same measurement - the total height of the tire when mounted and inflated.

Q4: Does tire height affect fuel economy?
A: Yes, taller tires can reduce engine RPM at highway speeds but may decrease acceleration. Shorter tires have the opposite effect.

Q5: How does tire height affect speedometer readings?
A: Taller tires make the speedometer read slower than actual speed, while shorter tires make it read faster.