A dynamometer, a diagnostic and tuning machine that measures the horsepower and torque a vehicle puts to the ground. Cars are strapped down with their drive wheels on heavy steel rollers, allowing tuners to run the engine through its rev range under load to map fuel and ignition curves safely.
Heard on the job
Let's strap it to the dyno and see if that new cam actually makes power.
Insider tip
Wheel horsepower measured on a chassis dyno is always lower than the engine horsepower claimed by manufacturers due to drivetrain loss.
Also heard as
- dynamometer
- rolling road