I believe with the top or 1/2 of the bypass removed, the turbine simply gets more air. While max RPM settings with and without 1/2 of the bypass are the same, performance is very definately better. I have tested on the Flash, MB-339, Skymaster L-39 and Skymaster Hawk all with the same results. . .hope this helps.

Happy New Year to all. . .

Eric Clapp
Jet Central Micro Turbines
Lifetime Warranty