Most of the better engine dyno have the RPM per second rate of acceleration options, I like 300 or 600 RPM per second depending on many things in the motors, street pump gas slower, race only faster with a narrowewr RPM band for the pulls on the race motors.
One of the Studka brand engine dyno I use to use was horrible about controlling the engine RPM when you were advancing the throttle to WOT before starting the pulls, I had to learn to advance that throttle SLOWLY before starting the test.
On the DTS and Super Flows dynos that wasn't an issue