1. What is a Wheel HP to Crank Calculator?

Definition: This calculator estimates engine crank horsepower based on measured wheel horsepower and drivetrain loss factor.

Purpose: It helps automotive enthusiasts and professionals determine actual engine power from dyno measurements.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( CHP \) — Crank horsepower (engine output)
• \( WHP \) — Wheel horsepower (measured at wheels)
• \( DTL \) — Drivetrain loss factor (typically 0.10-0.15)

Explanation: The formula accounts for power lost through the drivetrain (transmission, differential, etc.) to estimate the engine's actual output.

3. Importance of Crank HP Calculation

Details: Understanding crank horsepower helps in engine tuning, performance comparisons, and vehicle modifications.

4. Using the Calculator

Tips: Enter your dyno-measured wheel horsepower and estimated drivetrain loss (default 0.15 for RWD). DTL should be between 0 and 0.5.

5. Frequently Asked Questions (FAQ)

Q1: What's a typical drivetrain loss factor?
A: Typically 10-15% (0.10-0.15) for RWD, 15-20% for AWD, and 12-18% for FWD vehicles.

Q2: Why measure WHP instead of CHP directly?
A: WHP represents actual power reaching the wheels, which is what moves the vehicle.

Q3: Does this account for all power losses?
A: It accounts for mechanical drivetrain losses but not other factors like altitude or temperature.

Q4: Can I use this for electric vehicles?
A: No, EVs have different drivetrain characteristics with minimal power loss.

Q5: How accurate is this estimation?
A: It provides a rough estimate. Actual crank HP can vary based on many factors.