I have a '97 Force 75hp on a 22' pontoon boat. It has a 15 pitch 3 blade prop on it. Max RPM I get is about 4800. I can't seem to get more than 15mph out of the boat. I know it's a pontoon boat but i'm thinking I should get a little more. It seems to me that the lower unit on the engine is very small resulting in a small prop compared to other engines of that HP. Am I just being an idiot and that's the way it is?<br />Any advice would be greatly appreciated.......