Ok, stopped by the flying field today on the way home from a boat race and flew the phoenix. The engine now purrs like a kitten at idle with the carb from the OS 75AX tached out at 14,200 with an APC 10X7 prop and the powerbox muffler from an OS 46 AX. The transition is now instantaneous from idle to top RPM. This is fast becoming my number one airplane now. She flies very nice and the engine while still on the rich side shows good power. Next week I'll try a few more props.