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  1. #1
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    Help me understand lift

    Hey guys. I have an old Stratos that I know isn't propped correctly and I'm hoping to go through the process of testing props from some buddies boats this summer to see what might work best for me.

    The question I have is about lift. I understand what bow and stern lift are, but I'm struggling to understand how we quantify each one during a test run and decide if we need more or less.

    My initial thought in comparing the ride in my boat to others is to watch how far forward or back the spray is coming from the sides of the boat at top speed. For example in my boat when I'm going as fast as I can at optimal trim the spray seems to be at about at the seats, if that makes sense. So I presume that means way too much of my pad is touching water. When I ride in other boats that are tuned in better it seems like the spray is starting at the rear compartments or even further back. When I watch boat commercials on tv they make it look like 3 inches of the boat are in contact with the water and the rest is in the air. The spray seems like it's almost coming from behind the boat on those ones.

    Is this the right way to be thinking about it? Ideally when you're in the driver's seat at WOT and you look to your right and straight down at the water it should be calm, and you should have to look behind you to see water spraying out to the side? Meaning in my case I have a bow lift problem because my spray is too far forward?

    Hopefully I didn't make that too confusing.

    What other things should be kept in mind concerning lift when testing props? I also have some mild to moderate leaning and control issues when I have a second person in the boat that I sometimes think go hand in hand with these lift issues.

    The boat in question is a 99 Stratos 201PE with a 05 200 Optimax on a 6 inch Pro High Jacker. The prop is a 23p Tempest that could use a little Croxton TLC. It goes about 58 right now. I feel mid 60s should be achievable. I've got the prop to pad set at what the guys on the Stratos boards recommended. I'm going to catch hell for this, but the tach doesn't work so I don't know my RPMs. Adding a vessel view mobile to the Opti so I can get cpu RPM readouts will be the first step when I start this process.

  2. Member
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    #2
    For me, it's simple and part feel or senses. For bow lift, how much trim to you have to give it to raise the bow, and how high can you lift it. Too many boats can't lift the bow enough without proper setback and prop. For stern lift, it's how high on the pad it is running, especially at part throttle. I can sense or feel how high the boat is running from the water surface.

    I'm curious how others describe it.

  3. Moderator 21XDC's Avatar
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    #3
    What Spray?



    Marks Props 317-398-9294, 1850 East 225 South, Shelbyville, Indiana 46176 propellerman59@gmail.com http://www.marksprops.com/index.html

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    #4


    So that's the goal, eh? I've got a long fricken ways to go if that's the case

  5. Member
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    #5
    One good thing about the rpm's you should get a warning horn when it hits 5750 and it will shut down at 5790 so it won't over rev too much. That boat should be able to run a 24" tempest maybe even a 25" prop depending on how heavy you load it so that 23 is probably junk that's why you don't have any lift.

  6. Member
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    #6
    Don't know much about stratos boats but you mentioned the model is a 201 is that the length of the boat 20'1" and what horse power is it rated for because in my opinion you should always put the max horse power it's rated for especially when your running a 20 foot plus I'm sure that boat is rated for more than a 200 so if you don't have the max horse power on it your results are going to be on the low side

  7. RIP Evinrude 1907-2020 JR19's Avatar
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    #7
    I would not get caught up in what a boat looks like running down the lake. If your looking to improve performance then gauge the prop based on how it actually performs and not what the boat looks like.
    Last edited by JR19; 03-22-2020 at 11:13 PM.

  8. Member
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    #8
    Quote Originally Posted by ranger z520 View Post
    Don't know much about stratos boats but you mentioned the model is a 201 is that the length of the boat 20'1" and what horse power is it rated for because in my opinion you should always put the max horse power it's rated for especially when your running a 20 foot plus I'm sure that boat is rated for more than a 200 so if you don't have the max horse power on it your results are going to be on the low side
    You are correct. This boat is max rated at 245. They came from the factory with 225 Evinrudes. So technically it is underpowered, and I realize that I won't get ultimate performance out of it, but I know it can do better than it's doing right now.

    They made the 201 for many many years and I think there was a time that 200hp was the standard that they came with, so I don't think I'm so far off. The guys on the Stratos boards said I'd be fine. Many of them recommended a 4 blade. One of the props I'm going to test this summer is a 24 Bravo 1 xs. Hoping that goes well.

    The reason for the under powering was a matter of circumstances. My previous boat got hit by a car in front of my house. The motor survived the accident and the insurance company made me keep it. The Stratos happened to be for sale with no motor in my tiny little rural South Dakota town... it was meant to be. There aren't many bass boats in these parts. I was lucky to be able to solve my dilemma.

  9. Member
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    #9
    Quote Originally Posted by JR19 View Post
    I would not get caught up in what a boat looks like running down the lake. If your looking to improve performance the gauge the prop based on how it actually performs and not what the boat looks like.
    I'm not worried about what it looks like at all. The boat is kind of ugly to start with I'm just trying to understand how to use some of these measures to know what I need to try next.

  10. Moderator 21XDC's Avatar
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    #10
    Speed packs air under the hull for added "Lift"... When the hull has under rated hp, Most cases a good 3 blade with good bow lift will be the best choice for top end.

    Marks Props 317-398-9294, 1850 East 225 South, Shelbyville, Indiana 46176 propellerman59@gmail.com http://www.marksprops.com/index.html

  11. Member fishnfireman's Avatar
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    #11
    Quote Originally Posted by 21XDC View Post
    What Spray?


    Duck Hunting ??
    Hopefully thats just for show.

  12. Member H22BASS250SHO's Avatar
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    #12
    BINGO!
    Quote Originally Posted by JR19 View Post
    I would not get caught up in what a boat looks like running down the lake. If your looking to improve performance then gauge the prop based on how it actually performs and not what the boat looks like.

    2018 21' GatorTrax Strike Series, 250 Yamaha SHO

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    #13
    Quote Originally Posted by redxdu View Post
    I'm not worried about what it looks like at all. The boat is kind of ugly to start with I'm just trying to understand how to use some of these measures to know what I need to try next.
    Red,
    Before you start testing, get yourself set up so that you are able to know your RPMs and water pressure, than start testing based on the stats that you find when running at WOT and holeshot.
    Perhaps, you may find that your JP needs to be twitched a bit, but make sure that the props you are testing are properly blueprinted and balanced, which that would really help the current 1 you have.
    BTW, in the picture, Mike is just trying to run over as many jet skies as possible in 1 run, but if you were to bring that bow down about 18", you would notice the 'spray trail' would be somewhere just behind the seat back, not pushing water.