1. What is Frequency to Speed Calculation?

The frequency to speed calculation converts rotational frequency (Hz) to vehicle speed (mph) using gear ratio and tire circumference. This is useful for automotive diagnostics, performance tuning, and sensor calibration.

2. How Does the Calculator Work?

The calculator uses the following equation:

Where:

• \( \text{Frequency} \) — Rotational frequency in Hertz (Hz)
• \( \text{Gear Ratio} \) — Final drive ratio (dimensionless)
• \( \text{Tire Circumference} \) — Tire circumference in inches
• \( 60 \) — Converts Hz to RPM (minutes)
• \( 63360 \) — Converts inches to miles

Explanation: The equation converts rotational frequency through the drivetrain to linear vehicle speed, accounting for gear reduction and tire size.

3. Importance of Speed Calculation

Details: Accurate speed calculation from frequency is essential for vehicle speed sensors, cruise control systems, and performance monitoring. It helps verify sensor readings and diagnose drivetrain issues.

4. Using the Calculator

Tips: Enter frequency in Hz (typically from wheel speed sensor), gear ratio (final drive ratio), and tire circumference in inches. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: How do I measure tire circumference?
A: Measure from ground to axle center (rolling radius), multiply by 2π, or use manufacturer specifications adjusted for inflation pressure.

Q2: What's a typical gear ratio?
A: Passenger cars typically have 3-4:1 final drive ratios, while trucks may have 4-6:1 ratios.

Q3: Can I use RPM instead of Hz?
A: Yes, but divide RPM by 60 to convert to Hz before using this calculator.

Q4: How accurate is this calculation?
A: Accuracy depends on precise gear ratio and tire circumference measurements. Tire wear and inflation affect actual circumference.

Q5: Does this account for transmission gear?
A: No, this uses final drive ratio only. For transmission-included calculations, multiply by current gear ratio.