Who are you trying to kid. If you think an engine is just an Air Pump then by your own definition the only way to increase HP per CI is through Volumetric Efficiency.
Throwing parts at an engine will only get you so far.......
I didn't know it was April Fools Day. Shoot, if it's not moving air, let's plug the carb and exhaust - stuff some rags in there. Shouldn't effect HP at all, after all, we know air flow doesn't matter :D
