I have a Goldberg Skylark 70. It flys great with my OS .75 AX engine, however, I've been toying with the idea of putting a good four stroke engine on that plane.

Based on your experiences, what engine would you guys recommend I use for this plane? Don't forget, the OS .75 AX is a power house engine and I enjoy the performance of this plane with this engine. I just want to put a good four stroke on it to gain some experience with four strokes.

As you can see from the below list, I have several with OS two stroke engines from .46 to 1.20 (well I didn't list the two .46's and one .50 but they are in my "fleet" and the 50 is going on the Flying Thingz Skycutter flying mower).

Thanks for your suggestions.

CGr.