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Old 06-10-2013, 08:45 PM   #9
ishoot308
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Originally Posted by chasedawg View Post
I have a 2550 Bennington with a 300 Verado. Out of the box performance before broken in my GPS read 49.8 MPH at 5900 RPM. I had full tank of gas and just myself. The engine is rated at 6200 RPM. The prop is a Entergy 18 pitch prop. I was informed that if I drop down one pitch to a 17 or 16 pitch that I could break 51 MPH. Anyone have any experience with changing prop pitch?
Going down a pitch will raise your RPM but will most likely slow your speed down a bit. Your engine is rated for 5800- 6400 RPM at WOT. Your rev limiter should kick in at 6400. With pontoon boats you want to prop to the higher end of your rating so when loaded the engine performs well. You would need a 19P for faster speeds but your RPMs would be too low and I would not recommend it. If anything you could go down a pitch to raise your RPM's slightly but you may lose a mile per hour or two. Your pretty good where you are at, if anything try a different style prop, I am not that familiar with Mercury props but am sure there are a lot to choose from.

Dan

Edited to add this: http://www.mercurymarine.com/engines...letin/?ID=729&
Here's a performance report from Mercury using their 300 Verado on a Bennington very similar to yours. As you can see they used a 16P Enertia prop and got 6250 at WOT but speed was slightly slower than yours at 47.8 MPH. I would go for the higher RPMs and give up the mile per hour or two simply for engine longevity.
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Last edited by ishoot308; 06-10-2013 at 09:39 PM.
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