Ramp Runs

Does the dyno perform the ramp run itself? You just tell it what to rev to and the rate of ramp.

Whlle there may be dyno's that control the engine completly, most of the time, the operator instructs the dyno to begin a ramp run (measure from one RPM to another), and in the case of a load controlled dyno, the rate at when the Engine Speed should be allowed to change. Once started, you go to wide open throttle (WOT), or whatever throttle you want to use, and the dyno assumes control of holding the speed / ramp as designated.

On an inertial dyno, there is often a brake that can help retard the roller until you've reached full throttle, then the operator indicates it should begin recording the run.