1. What is Wheel Horsepower?

Wheel Horsepower (WHP) is the actual power that reaches the wheels after accounting for drivetrain losses. It's typically 10-20% less than the engine's crank horsepower due to mechanical losses in the transmission, differential, and other drivetrain components.

2. How Does the Calculator Work?

The calculator uses the WHP formula:

Where:

• \( Crank\ HP \) — Engine horsepower at the crankshaft (hp)
• \( Drivetrain\ Loss\ Percentage \) — Fraction of power lost in drivetrain (typically 0.15 for 15%)

Explanation: The equation accounts for power lost between the engine and wheels due to friction and mechanical inefficiencies in the drivetrain.

3. Importance of WHP Calculation

Details: WHP represents the actual power available to move the vehicle. It's crucial for performance tuning, comparing vehicle performance, and understanding real-world power delivery.

4. Using the Calculator

Tips: Enter crank horsepower in hp and drivetrain loss as a decimal (e.g., 0.15 for 15%). Typical drivetrain losses are 15% for RWD, 12% for FWD, and 20% for AWD vehicles.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between crank HP and wheel HP?
A: Crank HP is measured at the engine's crankshaft, while wheel HP is measured at the wheels after drivetrain losses.

Q2: What are typical drivetrain loss percentages?
A: Front-wheel drive: ~10-12%, Rear-wheel drive: ~15%, All-wheel drive: ~20-25%.

Q3: Why does WHP matter more than crank HP?
A: WHP represents the actual power moving your car, making it more relevant for real-world performance.

Q4: How is WHP measured?
A: WHP is measured on a dynamometer (dyno) by applying resistance to the wheels and measuring the force required.

Q5: Can WHP be higher than crank HP?
A: Normally no, but some dyno readings can appear higher due to measurement differences or correction factors.