Too much prop slip? What is too much?
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06-21-2016, 05:30 AM
#13
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Trying to figure out why boat is so slow. Current setup on my 28' Advantage V hull is 700hp(dyno proven) 1.5 ratio XR upper and -1 IMCO lower turning 26" and 28" B! 4 blades. I am seeing around 20-22% prop slip throughout the mid and upper rpm ranges. I have tried a std length lower with no change. I have tried a -2 lower which picked me up a couple mph, but blew the prop out pretty bad getting on plane. I have also tried a 27" Hydromotive 4 blade which I could blow out at will. I can turn the 26 at 5400 rpm and the 28 at 5100 rpm with around the same top speed of 71mph.
Here is where I think the problem is. The bow of this boat is heavy, I just can't get it out of the water. I cannot even trim it up high enough to make it porpoise. Once the boat starts coming out of the water, I can keep trimming up until the prop blows out without really changing the attitude of the boat any. It has always been this way with every different setup I have had on it. Would a 5 blade prop help? If so, what brand and pitch? Is 20% prop slip excessive? Transom has a small notch, but would an extension box or ITS help? I realize that this is not the fastest hull out there, but I think I should be closer to 80 than 70. I keep throwing more power at it with very little improvement in mph.
Thanks in advance for the help
Here is where I think the problem is. The bow of this boat is heavy, I just can't get it out of the water. I cannot even trim it up high enough to make it porpoise. Once the boat starts coming out of the water, I can keep trimming up until the prop blows out without really changing the attitude of the boat any. It has always been this way with every different setup I have had on it. Would a 5 blade prop help? If so, what brand and pitch? Is 20% prop slip excessive? Transom has a small notch, but would an extension box or ITS help? I realize that this is not the fastest hull out there, but I think I should be closer to 80 than 70. I keep throwing more power at it with very little improvement in mph.
Thanks in advance for the help
Call me and we can talk or email me
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Phone is 716 366 0922
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Jj
06-22-2016, 03:12 PM
#14
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Call me and we can talk or email me
I have the perfect solution to your problem
My name is jj
[email protected]. My email
Phone is 716 366 0922
Call me and I have a solution to your problem
I am glad to help
I have a answer to all your problems
Jj
I have the perfect solution to your problem
My name is jj
[email protected]. My email
Phone is 716 366 0922
Call me and I have a solution to your problem
I am glad to help
I have a answer to all your problems
Jj
06-22-2016, 03:15 PM
#15
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Creepy
06-23-2016, 03:53 AM
#16
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07-06-2016, 06:00 PM
#18
Just a quick update. I installed an 1 1/2" spacer and went out testing with my 28P Bravo 1. It picked up a couple mph with the same rpm. Running 75 @ 5200 for about 2 miles when it decided to snap a tooth right off one of the upper gears. I guess it was successful. Sort of.
07-06-2016, 08:03 PM
#19
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Just a quick update. I installed an 1 1/2" spacer and went out testing with my 28P Bravo 1. It picked up a couple mph with the same rpm. Running 75 @ 5200 for about 2 miles when it decided to snap a tooth right off one of the upper gears. I guess it was successful. Sort of.
