Seeking advice on a prop for speed.

[Jay69mx2000]

I have just purchased a 1991 cheetah 2000lsc 20 foot cuddy. 4.3 2bbl alpha 1 gen 2 . My current prop is a 1916p19. With 2 adults and 2 teen boys we ran 4370rpm wot at 36 mph. The boat planes quickly and pulls a tube well but will porpise if I try to trim anymore. It also has one of the hydrofoil fins on it. Should I loose the hydrofoil? And also I am looking at the solas hr titan 3 should I go down to a 17 or just leave well enough alone? Thanks.

 

[Chris1956]

I would try it without the whale tail. Your boat is probably stern heavy, but the porpoising is not usual. BTW - it sounds like you have the right pitch prop, unless you normally run with less people.

 

[steelespike]

Try it without the foil, hole shot will probably be slower but may respond better with trim.
What hp is the 4.3? Has the hull had any major work done on it?

 

[littlerayray]

Welcome to I boats and if you switch to a 3 blade prop go up 1 or 2 inches in pitch

 

[Jay69mx2000]

The boat seems all original. My motor is not marked for horsepower but the manual that came with it says its either 155 or 175 prop horsepower it has a 2bbl and no marking indicating it is a lx so I am figuring it is 155hp. I am removing the foil and taking it out tonight . As far as I can tell my current prop is 19 pitch x 14.5 it's a 3 blade in perfect condition.