Is there anyway to post pictures? The exhaust could be an issue, prop could be an issue also. There are alot of things that could be whats holding it back, it does sound like the boat is really big ( so I wouldn't consider it to be a race boat, but the engine you have should push it nicely). Pictures of the engine compartment and engine and pictures of the transom or back of the boat would be great. If you remove the prop most of them say what they are on the end under the nut.


Paul