Prop difference?

[cfelton]

Been looking around and now Im confused on what prop to try. Pretty sure I need a 19 pitch but what diameter? They range from 13, 14, 14.1/2,14 5/8,15 and so on. Ive got the old alum prop that probably came on the boat but its not in too good a shape. Its been painted a dozen times and I cant see anything on it. What do you all suggest I try.

[spareparts]

Swap props with your buddy. Run them both again and see what happens. Is that elite a four blade prop?

[Destroyer]

Originally Posted by spareparts

Swap props with your buddy. Run them both again and see what happens. Is that elite a four blade prop?

X2 That was going to be my suggestion, but Spare beat me to it. But I'm still sticking to my original comment about too much pitch. I agree with everything that everyone else has said about cupping, rake, timing, weight, drag, etc, but I also believe in the KISS principal. (Keep It Simple Stupid) And right now, the simplest thing is to switch props with a known 19P prop and see how your boat (and your friends) performs with the prop change. It's a simple check and it costs nothing and that's always a good thing.

[spareparts]

the Mirage prop would be my recommendation as well

[cfelton]

What do you think about the size. 15 x 19 looks like the size most chosen.

[spareparts]

A 17 would put you in the mid 30's(too slow), a 19 would put you in the low 40's

[cfelton]

How about the diameter, does 15 inch sound right? I'll probably go with a 19 pitch for speed and economy. I don't pull skiers or a tube very much so I guess Im trying to get more milage and top end speed. My engine kinda sounds like its straining running WOT. If my buddy will swap props for a day maybe Ill try that and see how that does. I know his prop is a 19 pitch, not sure of the diameter.

[THEFERMANATOR]

What do you want out of the boat? I think the large diameter props are good for all aorund useage, and really good for cruisng efficiency. Props with alot of rake are good for lifting the bow and top speed, but not always good for planing out and cruising as they tend to popoise at cruise on some hulls. 4 blade props have great holeshots, good cruisng efficiency, but tend to lack on the top end because they tend to lift the stern and not air the bow out on the top end.

I like the MIRAGE style prop for offshore boats as they have so much bite, hold so steady in the water, while maintaining good cruisng efficiency. You may need to drop down to a 18 pitch with a large diameter prop as the larger diameter increases bite and reduces prop slip, which makes the prop run like a prop of a larger pitch.