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