Here is my problem I own a 1980 open bow 176 ssv Glastron. Top speed used to be 50+mph with speed prop on (14dia 19pitch Aluminum). Now in 1998 the engine was rebuilt and things were never the same since. The comression spark everything seemed good but the power speed and performance was terrible. Ten years later in 2008 I had had enough of the guy who rebuilt it and took it to another place (5th different place). This guy was honest and worth my time and money this time. After dyno testing the engine he found it was putting out less the 50% more like 35%. So the guy tore the head off to find the pistons were put in backwards! Much to his and my dismay the engine actually ran with the pistons backwards ( had it been the 1979 model the pistons would have stopped by hitting the head dumb luck for me). So the guy fixed the problem and off to the lake. Wow finally the boat works like it should. Luckly the backwards pistons caused no internal damage. (That is the history but here is the promblem) My speed has dropped to 35mph with top rpm of 5500 5600 with the prop I mentioned (14x19)) I know The fuel line has been piched a few time but that doesn't seem like it could be that. Any ideas? I should get the same results with this prop as before but maybe that isn't the right prop anyway. All the help I can get please?
