I have a 1994 chris craft concept with ford efi 5.0l with cobra sx outdive. Boat ran fine for an hour and then would not go above 3500 at wot. It would then fall to about 2800 rpm occasionally rpms would go up an fall back. Runs fine at 2800rpm and below. Also notice good amount of hot water in bilge. My outdrive is also stuck in forward gear (cone clutch. cables are perfect), but that's another problem.