prop size

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Chum Bucket
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Joined: Sat Feb 06, 2016 3:14 pm

Post by Chum Bucket »

"I have a feeling you got the numbers reversed. 21 diameter by 22 5/8 pitch makes more sense." A lot of people say that, but my numbers are not reversed. I bought these 23 x 21 no cup props to replace the ones that 'disappeared' during shipping. I added a cup, then a little more and finally rounded the tips to where I'm at today. I sea trialed the boat with 4 blade, 22 x 22 cupped and barely hit 2800. When I bought my current props, I just assumed I would have them worked to 21 x 21 with a heavy cup until the prop guru strongly disagreed. His philosophy is to turn the biggest diameter wheel the boat and HP allows and make adjustments from there. He said pitch is not a true replacement for surface area, but a overall compromise. I'm now a believer.
Kevin D "Chum Bucket" 1979 Sportfish 3208T 320hp Cats
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