Today was my second day of flying the 2300. I am running a MA 18-8, turning up at 7700. I was successful in adjusting the carb to get satisfactory performance without any pumps or regulators. I then switched to an 18-6 prop, which turned over 9000 and really sounded nice. I had three flights and three dead stick landings. I would be at about 1/2 throttle and the engine would just die. One time it happened in level flight, and I was able to cut the throttle and get it going again, for a little while. I had really good smoke trail and never ran lean. I put the 18-8 back on and tweaked the needles again, just a little, and had three more flights without a hitch. I would say that had I only bought an 18-6 prop, I would think this engine is junk, but it runs really good on the 18-8. I'm burning 10% powermaster and using an F plug. I had another engine do this very thing. That was an ASP 1.08. I gave up on that engine after too many dead sticks. Anybody have any ideas as to why a lighter prop load would cause flameouts? I am baffled.[]