A dynamometer is a device that can measure force, power, or speed—so you can figure the engine output and how usefulness was modification.

Like most test equipment, a dynamometer (or dyno for short) helps isolate and quantify a particular parameter (in this case the engine’s power output) from overall vehicle performance. Why do you need to do that?

It has many benefits:

1. possible to see the gain after modifications
2. useful for live tuning engine control unit on road-like conditions – steady state, ramp run
3. emissions testing
4. good for testing cars at high speeds is safe conditions