25% slip
#1
Thread Starter
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Joined: Aug 2021
Posts: 248
Likes: 99
From: St. Louis, MO
27’ Fountain single step
18.5” X Dimension
Bravo upper standard height IMCO lower
1.50 ratio
280 K planes
28p B1 - new out of the box
540BB, Dart heads/intake, hyd roller w a 1050 ProSystems. Made 640/630tq with standard headers so not sure what it’s actually turning at the shaft.
Had a 26p B1 on it and the boat will run 72-73 @5800. Picked up a new 28p B1 and it runs 72-73 @5400. Same mph and roughly same slip %. I only got to run it a couple times with the new prop before the season ended.
Plan to really do some testing this spring to feel the boat with different trim / tab adjustments and capture slip numbers. I’d really like to test mid range cruise. I know it should be higher, but may help put together what the hull likes. Typically at WOT I’ve got the tabs all the way up and drive around 4-4.5. Maybe I’ll get it dialed in with seat time, but wanted to open up props for conversation.
I contacted Brett last fall and I couldn’t find the email
so maybe he called me back, either way he seemed to lean towards me needing to address the slip before fixing it with a prop. Maybe he’s on to something because the new B1 made no difference other than a drop in RPM - which was a positive.
I see a lot of Fountains running Hydromotive and one guy said a Maximus really helped, dropping slip by about 10%.
The boat runs fine, but I’d really like a little more top end out of it and feel it’s capable.
Thanks
18.5” X Dimension
Bravo upper standard height IMCO lower
1.50 ratio
280 K planes
28p B1 - new out of the box
540BB, Dart heads/intake, hyd roller w a 1050 ProSystems. Made 640/630tq with standard headers so not sure what it’s actually turning at the shaft.
Had a 26p B1 on it and the boat will run 72-73 @5800. Picked up a new 28p B1 and it runs 72-73 @5400. Same mph and roughly same slip %. I only got to run it a couple times with the new prop before the season ended.
Plan to really do some testing this spring to feel the boat with different trim / tab adjustments and capture slip numbers. I’d really like to test mid range cruise. I know it should be higher, but may help put together what the hull likes. Typically at WOT I’ve got the tabs all the way up and drive around 4-4.5. Maybe I’ll get it dialed in with seat time, but wanted to open up props for conversation.
I contacted Brett last fall and I couldn’t find the email
so maybe he called me back, either way he seemed to lean towards me needing to address the slip before fixing it with a prop. Maybe he’s on to something because the new B1 made no difference other than a drop in RPM - which was a positive.
I see a lot of Fountains running Hydromotive and one guy said a Maximus really helped, dropping slip by about 10%.
The boat runs fine, but I’d really like a little more top end out of it and feel it’s capable.
Thanks
#5
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Joined: Aug 2021
Posts: 248
Likes: 99
From: St. Louis, MO
Thought about a GoPro in the side mount may help. I do know once I trim it up it starts to chine around 70, so I have a feeling it’s on the pad.
#6
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Joined: Oct 2000
Posts: 3,775
Likes: 638
From: Lakewood, NY, USA
Not a Fountain owner but my Velocitys always ran faster with Hydromotive. Reggie used to ship his single engine boats with a Hydromotive prop until Mercruiser put the screws to him and made him use Bravos.
Padraig
Padraig
#7
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Joined: Jul 2009
Posts: 8,527
Likes: 706
From: Taunton Ma
below 80 the imco nose cone hurts more than it helps. I tried one on a 27 fountain years ago, went to a -2 and it was 1-2 mph slower than the stock lower.
Every other boat I’ve ran an imco on that was slower than 80 or didn’t need the shorter lower ran slower.
Every other boat I’ve ran an imco on that was slower than 80 or didn’t need the shorter lower ran slower.
#8
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Joined: Aug 2021
Posts: 248
Likes: 99
From: St. Louis, MO
Thanks. I haven’t looked into it much but could I put on one of those aftermarket nose cones possibly?
#10
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Joined: Aug 2021
Posts: 248
Likes: 99
From: St. Louis, MO
Mainly from ignorance. Did some reading and see your point. I am curious though your thoughts on switching on the IMCO for a B1 or XR. Thank you



