I am only getting 25-27 mph out of my 16 ft aluminum boat with a 50 hp. It rides nose down when it is trimed in the middle and when I trim it up it speeds up to 25-27 and then starts to Cavitate. 5500-6000 rpm equal 25-27 mph What is the deal?

Does this mean I need to mount the engine lower on the transom? Change angles that the motor is mounted at? Or What? Any suggestions?

Scott

Trim your motor so it's parallel to the transom. Look and see where a line would fall on the motor coming straight back off the bottom of your boat. How much of the lower unit would be in the water?

How old is this boat and motor? Is the motor a short shaft or long shaft? I suspect it is a short shaft if it rides nose down and cavitates when you trim up.

I slid the motor down some on its mount and replaced the fuel filter. It ran a lot better still only 27 mph max speed but the nose came up out of the water and it ran over the top of the waves rather than through them. I suspect I may get 30 out of it on a smooth lake. Much better now though...thanks for you reply

Scott

Two important things to correct. First, make sure that the cavitaion plate on your engine is level with the bottom of your boat. Raise or lower the engine to adjust the height. Secondly, it sounds that you might have an incorrect pitch prop for that boat. If you have a tach and if your rpm's are 6000 at WOT then I would change prop and go up a couple of inches in pitch. One inch equals about 200 rpm reduction if you are increasing the pitch.

Also, if your boat is cavitating then you need to move the engine in one notch. Cavitating is not good. I'm assuming you have to change the trim manually. That is it not electro-mechanical?

It has an electric trim...The prop idea sounds good. Do you think that would give me a little more speed?

Scott