Wheel Horsepower Calculator
Calculate horsepower delivered to wheels accounting for drivetrain losses
Calculate Wheel Horsepower
Engine horsepower as measured at the crankshaft
Simple mode: Use overall component efficiencies
Wheel Horsepower Results
Power Breakdown
Component Efficiencies
Drive Type: Rear-Wheel Drive (RWD)
Components in power transmission: Gearbox → Propeller Shaft → Differential → Drive Shaft
Typical efficiency range for RWD: 80-85%
Example Calculation
Understanding Drivetrain Loss
Engine Power
Generated at the crankshaft (BHP)
Drivetrain Loss
Power lost in transmission components
Wheel Power
Available power at driving wheels (WHP)
Efficiency by Drive Type
FWD: Most Efficient
Fewer components, shorter power path
RWD: Moderate Loss
Additional propeller shaft losses
AWD: Highest Loss
Transfer case and multiple drivelines
Understanding Wheel Horsepower
What is Wheel Horsepower?
Wheel horsepower (WHP) is the actual power delivered to the driving wheels of a vehicle. It's always less than engine horsepower due to losses in the drivetrain components that transmit power from the engine to the wheels.
Formula
WHP = ηdrivetrain × EHP
Where ηdrivetrain is drivetrain efficiency and EHP is engine horsepower
Drivetrain Components
- •Gearbox: Transmits power at different speed ratios
- •Propeller Shaft: Connects gearbox to rear axle (RWD/AWD)
- •Differential: Distributes power between wheels
- •Drive Shaft: Final power delivery to wheels
Why It Matters
Wheel horsepower is the true measure of a vehicle's performance capability, as it represents the actual power available for acceleration and speed.