Well, thanks montague (and others). that's why i'm trying all of this. I feel as though the contender, while weighing only 6 pounds, is underpowered with this engine. It is, however, at the bottom of the recommended list by the manufacturer. With the short stubby wings of the contender, a lot of air must pass under them to keep the ship afloat. I feel as though if I could turn more prop at slightly higher RPM's, then I could pull the plane with a little more authority. I want to keep this engine on this plane, but I feel as though I need to do something. one thing I've figured out is to land it faster. I think that may be a characteristic of the plane anyway.