Thanks for the clarification (less power at higher rpm); I seem to remember claims of 10 % additional power throughout the rpm spectrum.Damocles,
From what I remember from the .net posting by Eagle Mike and Mike Coe (MC mod), the additional power 'signs off' at about 6200 rpm! Not redline (7500 rpm).
As to how? I'll only suggest that it allows a 'longer Draw' of fresh intake mixture at the lower RPM's.
As to the "longer draw," hard to visualize when the exhaust valves close earlier in the cycle, but indeed: Could certainly be the case.