1. What is Flywheel vs Wheel Horsepower?

Definition: This calculator converts engine horsepower (measured at the flywheel) to rear wheel horsepower, accounting for drivetrain power losses.

Purpose: It helps automotive enthusiasts and professionals estimate actual power delivered to the wheels after drivetrain losses.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( WHP \) — Wheel Horsepower (power at the wheels)
• \( FHP \) — Flywheel Horsepower (engine power)
• \( DTL \) — Drivetrain Loss Factor (typically 0.15-0.2 or 15-20%)

Explanation: The formula accounts for power lost through the transmission, differential, and other drivetrain components.

3. Importance of WHP Calculation

Details: Wheel horsepower represents the actual power available to move the vehicle, which is crucial for performance tuning and comparisons.

4. Using the Calculator

Tips: Enter the flywheel horsepower and drivetrain loss factor (default 0.15). The DTL should be between 0 and 1 (15% = 0.15).

5. Frequently Asked Questions (FAQ)

Q1: What's a typical drivetrain loss factor?
A: For rear-wheel drive: ~15-17%, front-wheel drive: ~10-12%, all-wheel drive: ~20-25%.

Q2: Why is WHP lower than FHP?
A: Power is lost through friction in the transmission, driveshaft, differential, and other components.

Q3: How accurate is this calculation?
A: It provides a good estimate, but actual dyno testing is needed for precise measurements.

Q4: Can I calculate FHP from WHP?
A: Yes, rearrange the formula: \( FHP = WHP / (1 - DTL) \).

Q5: Does this account for different transmission types?
A: The DTL factor should be adjusted based on transmission type (manual vs automatic).