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the boat doctor, hank johnston

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how do i e-mail a question to hank johnston, the boat doctor on this site?? i have done it before, but now i don't see how i can?? i have a prop question!! thanks!! well why i am posting, let me ask you!! he says if you cup a prop, it will cut down the full throttle rpm's down by 150-300 rpm's! but, is that a 1 degree cup or what?? hope we have some prop guys on here?? thanks again!!
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   cajunbob
There is a difference in pitch degree and cup .
Making more cup should cut the rpm's down some.
If that doesn't work. Making the pitch bigger, say from a 21 to a 23 pitch would cut down the rpm's
Hope this helps
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Beast...I don't know if you are close to Houma...if so go see Baggy(Pat) at Baggy's propeller service...I've used him forever...really knows his stuff...I have called him on occasion and he sometimes can solve your problem over the phone...
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   Kyle35
Usually you will gain 100 rpm's for every pitch down (25P to 24P) and lose 100 rpm's for every pitch up (24P to 25P).
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