new prop selection

[tmusvi]

32' 8" hatteras sportfisherman express, tuna tower need help on new prop size and pitch
4 or 3 blade? who to contact, 454 gasers marine power

[REBrueckner]

One key piece of information for sizing new props is current prop size and performance. Even "new" standards might not apply since boats get heavier over the years....from water absorption and all the junk we tend to accumulate....and on rare occasions, big catches of fish!!! (at least in our stories)

[sofarelli]

I am running 19"x19" 4-blade props on my 32' Hatt.

[Jackman]

I would use the largest diameter prop you can fit in the pockets leaving about 1.5 inches between the tip of the blade and the hull....and still maintain WOT specs for the engines. When I had Crusaders (454) in my 32' Hat I had either 20x18 or 19x19. The only problem with 19x19 is, as far as I've seen, michigan props don't come in 19" and you have to take an inch off of them. I was not keen on changing the dynamics of the props in that manner.

Bottom line is I was always told that with prop pockets the optimum configuration is one that allows you to fill as much of the pockets with prop as possible with the correct pitch at that diameter and still maintain WOT specs.

Best way to begin this is to buy a cheap set or borrow a set from a friend and work your way into finding out what will work for you. I would start at 19 0r 20". Once you find out what the engines do with those diameters you generally will change about 200 rpms per inch of pitch. (What dom the engines do now with the current props? Thats an even better place to start.

Another important thing to do first BEFORE you mess with the props....Make sure your bottom is perfect and your engines are running as best as possible as well. You wouldn't want to spend the cash on sizing props with a fouled bottom or pour performing andgines.