Posts: 3480
Location: Elk River, Minnesota | With the prop that is on it, having it reworked will do very little as the blade geometry is not designed to be much more than a stock configuration. Cupping would help, but you would lose RPM, pushing you out of the pitch you could use. By the time you do all the tweaking on that prop to get something worthy to work with, you could purchase a different prop with the configuration you need, and already has the engineering in the prop to be efficient.
Your numbers are not too far off from max now and the speed you are getting is right in the ballpark, so I am thinking a 17 pitch would be about right. The ballistic might even give you a touch more top RPM, and...if the motor is mounted flush or one hole up, you can move that motor up another notch to gain another 100 RPM or so.
Now...if you are running 5700 with two people and gear, you are right where you need to be as if you run just by yourself you'd be hitting the 6000 mark which is the maximum for your motor.
If on the outside chance you find that the prop is turning too many rpms at top, then we can definitely move the motor up and go up in pitch. This would gain you top speed, but as with anything, there is always a trade off... here, it would be hole-shot, and the higher you move the motor, the less handling you have at trim. The nice thing about an aggressive prop design is it allows for higher motor heights without much sacrifice in handling...to a point. The boat rides higher and handles very well.
now...if you do a bit of exploring, powertech props have a huge selection of sizes and styles to consider. The blade geometry I would recommend would be something like an OMC raker...the only drawback to getting a raker prop is it will not have the right spline count to work. You will notice the blades are swept back a bit (called rake), and they are not huge round ears either... The design should have a decent amount of trailing edge cup (stern lift) and tip cupping (bow trim and handling). Most designs like this will have vent holes as well to help hole shot...
Lots of options and no doubt you can get into a prop that will do much more than your current set up now. If you do some calling around, you might be able to find a dealer that offers a demo prop program where you can try a variety of props in different designs, pitches and diameters. it is time consuming, but if you enjoy the process, testing, etc., it can be an enjoyable experience, and when you find the right prop for what you are looking for, the boat will just float along at cruising speed, will corner nicecly in a moderate turn, and will have the top speed you are looking for.
Steve
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 raker prop design.jpeg (8KB - 563 downloads)
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