Yeah, but we usually turn slower rpms up here because there isnt as much air for our engines. We run a lot leaner because of that up here, and cars lose about 15-20% of power, same as model airplane engines. A lot of full scale airplanes are turbo charged to make up for that. But you are right, there is less air for the prop to load, but there is also less power in our engines. We lose out in two ways but i do get around 18 lbs of thrust with a pro zinger 20x6.

Adam