need info: on changing from 4BL to 5BL
#1
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I'm thinking of trying a 5 blade prop, but not sure what size to try, currently running a 26 B1 at 5600 rpm, it gets the boat up on plane pretty good and top speed is good, a 28p B1 runs 5400 rpm little slower out of hole, but better cruise and top is about the same, I am looking a Hydromotive P5 28P, how will this prop act on the boat? gains, losses.
thanks
larry
thanks
larry
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I had a pair on my Fountain. Great for stern-lift., whereas your B1's lift the bow... a 28P5 is equivalent to a 30 B1...
probably too big, and do you want stern-lift on your cat?\
Carder
probably too big, and do you want stern-lift on your cat?\
Carder
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It has a lot of natural bow lift to it now, thats why I figured a
P5 instead of a P5X. Can the diameter be cut down to make up for the increase in pitch.
P5 instead of a P5X. Can the diameter be cut down to make up for the increase in pitch.
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Not always the case, more blades equal more drag and less speed, unless your hull design suffers from a very high slip factor, in general the Fountains do not suffer from this problem. Most often mid speeds go up with the added blades, but not always the top end, regardless of the brand of prop. I tested some Maximus 5 blades, and they run exactly the same top end speed and RPM as my Bravos, the 3500 RPM cruise was 6 MPH faster.
Last edited by RaggedEdge; 05-24-2008 at 06:46 AM.
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I chose the P5Xs with my shorties, but I always wondered if I should have went with the P5s. Reasoning was that I had a farily deep x-dim at 16 3/8 which I raised 2". Even with that Tom at Hydromotive said to go with the P5Xs because now I was only at the x-dim that the new fountains are coming from the factory with. Wish they had a loaner program, still would like to try.
I tried the Bravos. Not as great of hookup in the lower and mid-range, but no much difference on top.
I tried the Bravos. Not as great of hookup in the lower and mid-range, but no much difference on top.
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everyone on this thread is running the high pitch's than what I am running, I'm going to start a new thread about possible gear changes. Thanks for all the info: guy's
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01-31-2005 11:27 PM