The Turbo commander uses the same system. 2 speeds, both are very loud. I don't remember exactly but I think it was 85% and 100%. You change power to go faster, as stated above, more fuel equals a bigger bite and more speed.

On a model engine Juice, at low RPM the prop may spin like 1000 RPM and at full throttle, you could get max RPM depending on the engine, 5000 to as much as 20,000 on some of the racing engines. The prop does not change pitch so you have to increase the RPM to increase speed or climb power.