Engine to Wheel kW Calculator

Engine to Wheel kW Formula

The calculation of power at the wheels involves a simple formula that takes into account the power losses through the drivetrain:

\[ W(kW) = E(kW) - (E(kW) \times DTL) \]

Where:

• \(W(kW)\) represents the wheel kilo-watts,
• \(E(kW)\) denotes the engine kilo-watts,
• \(DTL\) is the drivetrain loss, which varies depending on the type of drivetrain:
  • 10% for front-wheel drive,
  • 15% for rear-wheel drive,
  • 20% for all-wheel drive.

What is Wheel kW?

Wheel kW is the net power output measured at the vehicle's wheels after subtracting the drivetrain losses from the engine's power output. This figure is closer to the actual power utilized for propulsion than the gross engine power figure.

How to Calculate Wheel kW?

To determine wheel kW, you first need the engine's power output in kW and the estimated percentage of drivetrain loss based on the vehicle's drive configuration (FWD, RWD, AWD). Use the formula above to calculate the net power available at the wheels.

Example Calculation

For a vehicle with 300 kW engine power and an all-wheel drive system:

\[ W(kW) = 300 - (300 \times 0.2) = 240 \text{ kW} \]

This means 240 kW of power is effectively available at the wheels for propulsion.

Understanding the difference between engine power and wheel power is essential for automotive enthusiasts, engineers, and anyone interested in the performance characteristics of vehicles. It highlights the efficiency of the drivetrain and the real-world power that contributes to the vehicle's acceleration and driving dynamics.