I have a 2005 15hp 4-stroke. The problem I'm having is the baot will not make plane. it is really close. The motor will only turn 4500 rpm at a wide open throttle. It should turn 5500 rpm at WOT. The boat is a Lowe FM165 it is aluminum hull 16'. the prop is a 9p a12. Not sure what the a12 stands...
