Dynamometers, also known as dyno, are small machines that are used for measuring torque, rotational speed and power output of the car engine. Apart from these basic functions, dynamometers are also used for tuning up the car.

Dynamometers are basically divided into two categories: engine dynamometers and chassis dynamometer. Engine dynamometer is the one that is attached directly to the engines. This type is used when the car engine is removed from the car to get an accurate reading. It is comparatively expensive and is mainly used by car manufacturers to test the longevity and reliability of the car engines. This kind of dynamometer gives a perfect solution to trouble shoot problems like insufficient torque, leaks, low horsepower, low engine performance and faulty engine.

Chassis dynamometer is the one that can measure horsepower while the car engine is still in the chassis. The tool is used to run the wheel on rolling roads or rollers to get the horsepower reading. This kind of dynamometer is used by the common car consumers but it fails to give the accurate reading. Just because the tool measures through the wheel, the reading gets affected by the transmission, tyres and driveline. Chassis dynamometer is used for identifying and verifying problems like low horsepower, overheating, speedometer accuracy, and emissions compliance.

Apart from main two categories, engine and chassis dynamometers, there are other two dynamometers that are widely used in the car industry. The first is the ‘towing dynamometer that is mainly used to transfer power from light cars to heavy commercial vehicles using a drive shaft.