Best prop to stop Ventilation during turns at almost any speed ?

Discussion in 'Outboards' started by cyclops2, Apr 29, 2014.

  1. cyclops2
    Joined: Sep 2010
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    cyclops2 Senior Member

    Which company has the best design to prevent ventilation ?

    Do not care about speed.
     
  2. gonzo
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    gonzo Senior Member

    Depending on the application there will be a variety of answers. On outboards and sterndrives, a properly designed hull with the anti-ventilation plate at the right height will prevent prop ventilation.
     
  3. powerabout
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    powerabout Senior Member

    lots of cup and rake
    its not exhaust getting back to the blades is it.
    What type of prop is it now
     
  4. cyclops2
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    cyclops2 Senior Member

    It is a Black Diamond Aluminum 3 blade 14.25" X 21" ?? Smuged .

    On a 5.0L 220 hp Mercruiser. Can ventilate at any speed or turn rate at any speed. Drive in or trimmed out

    Opinions on a Power Tech 4 blade with a high rake & cup. I was told the PTC4 would be one of the most difficult props to ever ventilate.
     
  5. powerabout
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    powerabout Senior Member

    as Gonzo says also has a lot to do with the boat and install of the drive.
     
  6. Mr Efficiency
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    Mr Efficiency Senior Member

    Try a cupped stainless prop to see what improvement you get.
     
  7. powerabout
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    powerabout Senior Member

    if the drive is installed high then all bets are off that you can fix it.
    Do you lose thrust or just hear the noise?
     

  8. Mr Efficiency
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    Mr Efficiency Senior Member

    I have experimented with engine heights on outboards and was a little surprised by how high you could go and still not have the prop "let go" ( on smooth water), just gain engine rpm, and probably a little boat speed. I/O is the same principle. But the test boat had cupped stainless, I once bought a twin outboard boat that played up badly with cavitation/ventilation, switched from alloy to stainless and never had any more trouble.
     
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