I guess you'd have to do dynamometer tests with and without, Bob, to see whether it helps. Piston ports give you lousy timing, and reed valves give you lousy volumetric efficiency. Using both together sounds like a very strange choice. Generally, if you want to make a 2 stroke give high power without supercharging, a rotary valve on the crankshaft alleviates both the port timing and volumetric efficiency problems. That is for high speed engines - rotary valves tend to be too expensive for cheapies. A reed valve directly into the crankcase is very good for low speed engines - volumetric efficiency isn't all that good, but it fixes the blow-back problem and gives correct intake timing as well (unlike ported intake systems).
