1. What is RWHP?

RWHP (Rear Wheel Horsepower) is the actual horsepower measured at the wheels of a vehicle. It represents the usable power that propels the vehicle forward, accounting for power losses through the drivetrain.

2. How Does the Calculator Work?

The calculator uses the RWHP formula:

Where:

• \( HP \) — Engine horsepower (crank horsepower)
• \( drivetrain\_loss \) — Power loss through drivetrain (decimal value)

Explanation: The equation calculates the actual power delivered to the wheels by accounting for mechanical losses in the transmission, differential, and other drivetrain components.

3. Importance of RWHP Calculation

Details: RWHP provides a more accurate measurement of a vehicle's actual performance capabilities than engine horsepower alone. It's essential for performance tuning, dyno testing, and comparing vehicle performance.

4. Using the Calculator

Tips: Enter engine horsepower (HP) and drivetrain loss as a decimal (e.g., 0.15 for 15% loss). Typical drivetrain losses range from 10-20% for rear-wheel drive vehicles, 15-25% for front-wheel drive, and 20-30% for all-wheel drive vehicles.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between HP and RWHP?
A: HP (horsepower) is measured at the engine crankshaft, while RWHP is measured at the wheels after accounting for drivetrain losses.

Q2: What are typical drivetrain loss percentages?
A: Typical losses range from 10-30% depending on drivetrain type: RWD (10-20%), FWD (15-25%), AWD (20-30%).

Q3: Why is RWHP lower than engine HP?
A: RWHP is lower due to power losses through the transmission, driveshaft, differential, axles, and other drivetrain components.

Q4: How is RWHP measured?
A: RWHP is typically measured using a chassis dynamometer (dyno) that measures the power actually reaching the wheels.

Q5: Can RWHP be higher than engine HP?
A: No, RWHP is always less than or equal to engine HP due to inherent drivetrain losses.