Power-to-weight Ratio
The power-to-weight ratio compares engine power with vehicle weight and gives an idea of how lively a car feels.
What is Power-to-weight Ratio?
It can be stated as kW per tonne, hp per tonne or as kilograms per hp. A light car with moderate power can feel as quick as a heavier car with more power. Torque, gearing and traction also affect real acceleration. Performance figures such as 0 to 100 km/h are influenced by power-to-weight, but also by launch traction and gearbox speed. Electric cars deliver strong torque from standstill, so they often accelerate faster than their power-to-weight ratio alone suggests. For towing, a good ratio of power to total combination weight matters.
How it works
Dividing power by weight shows how much power is available to move each kilogram.
Why it matters for your car
Driver and passengers change the ratio noticeably in small cars. Some licence categories for motorcycles use power-to-weight limits.
Other terms
- Drive Shaft (Half Shaft)
- Green Card (International Motor Insurance)
- Historic Vehicle Registration (Classic Plates)
- Hydrogen Combustion Engine
- LED Headlight
- Liftback
- Long-term Car Storage
- Megawatt Charging System (MCS)
- Number Plate Light (Licence Plate Lamp)
- Panel Gap
- Relay
- Roof Rails
- Seasonal Tyre Change
- Side Airbag
- Starting Handle (Crank Handle)
- Third-Party Liability Insurance
- Toe (Alignment)
- Turbo Lag
- Vehicle Winch
- WLTP (Worldwide Harmonised Light Vehicles Test Procedure)