Bobby Wilson at Cactus Aviation just received a new shipment of 3w 100's. But these are even a newer style that have been upgraded from 98CC's to 106cc's. When I was in Germany they had them on the test benches and they were turning 30x10 menzs props at 6,000 RPM. It is a very strong engine. It is also only 5.9 pounds. Maybe this will give you some food for thought.
Garrett Morrison.