1. What is the Corvette Speedometer Gear Calculator?

The Corvette Speedometer Gear Calculator determines the correct speedometer gear teeth count needed when changing axle ratios or tire sizes on classic Corvettes to maintain accurate speedometer readings.

2. How Does the Calculator Work?

The calculator uses the following formula:

Where:

• \( Axle Ratio \) — Rear axle gear ratio
• \( Tire Revolutions Per Mile \) — Calculated from tire diameter
• \( Driven Gear Constant \) — Transmission-specific constant (typically 6-8)

Explanation: The equation accounts for how changes in gearing and tire size affect the speedometer cable rotation speed.

3. Importance of Correct Speedometer Gear

Details: Using the wrong speedometer gear can cause inaccurate speed readings, affect shift points in automatic transmissions, and potentially lead to speeding tickets.

4. Using the Calculator

Tips: Enter your rear axle ratio (e.g., 3.55) and tire diameter in inches (measured or from manufacturer specs). The calculator will recommend the closest available gear tooth count.

5. Frequently Asked Questions (FAQ)

Q1: What if my calculated gear tooth count isn't available?
A: Choose the closest available gear. Small differences can often be corrected with speedometer calibration.

Q2: Does this work for all Corvette models?
A: This works best for classic Corvettes with mechanical speedometers (C1-C3). Later models may require electronic calibration.

Q3: How do I measure tire diameter accurately?
A: Measure from ground to top of tire with proper inflation and vehicle weight on wheels, or consult manufacturer specs.

Q4: What about transmission differences?
A: Different transmissions may require different driven gear constants. Consult your transmission manual.

Q5: Can I use this for other GM vehicles?
A: While the principle is similar, gear tooth counts and availability may differ for non-Corvette models.