IvoProp inflight adjustable question...

Discussion in 'Firewall Forward / Props / Fuel system' started by MadProfessor8138, Aug 19, 2019.

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  1. Aug 19, 2019 #1

    MadProfessor8138

    MadProfessor8138

    MadProfessor8138

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    I've flown fixed pitch,ground adjustable and a few constant speed props but I've never flown an inflight adjustable prop.
    I understand the theory for the most part on a 4-stroke.....set your rpm and adjust the manifold pressure.
    Thought I would ask how the prop is operated with a 2-stroke engine.....2-strokes can be peaky at particular rpm's etc...
    Do you set the engine to full throttle or 3/4 throttle and then use the prop to govern the engine speed by increasing or decreasing the prop load.

    I don't mean to sound totally ignorant on the issue but this is one area that I have no practical experience with....

    Kevin
     
    Last edited: Aug 20, 2019
  2. Aug 20, 2019 #2

    TFF

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    Sounds like a cat fight. I think setting to 85-90 percent and start jockeying with prop and power until you find a pattern you like. Then you can go to it. Then you can go full power and see how much pitch it can take.
     
  3. Aug 20, 2019 #3

    Hephaestus

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  4. Aug 20, 2019 #4

    MadProfessor8138

    MadProfessor8138

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    Yeah...I saw the constant speed add-on that they offer.
    I've also read that they've had some issues with it....how true this is I dont know.

    At this point,I'm just researching props and trying to learn as much as possible.
    I've plugged numbers into the prop calculator and can acheive a better than 1:1 ratio but cruise drops dramatically with a fixed pitch prop.
    The inflight adjustable or constant speed would give me great climb and cruise...best of both worlds.
    Once I get my Stork finished I would like to take it to OshKosh and enter the STOL competitions that they have.
    With its light weight,94 hp Rotax 670 and an adjustable pitch prop......it should be a serious contender.

    Kevin
     
    Last edited: Aug 20, 2019
  5. Aug 20, 2019 #5

    PW_Plack

    PW_Plack

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    Be really careful if your two-stroke uses pre-mixed oil and fuel. If you take too much pitch out of the prop and create a light load at high RPM, you'll wind up with bearings starving for oil. If you have oil injection, you might get away with it.

    Two-strokes are very picky about having the right combination of prop pitch and jetting. I'd stay away from variable pitch props unless you use a four-stroke.
     
  6. Aug 20, 2019 #6

    rv6ejguy

    rv6ejguy

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    I've got over 400 hours on my inflight adjustable IVO. In my application, I use about neutral pitch for takeoff, climb and pattern work (blade angle judged with an ammeter on the panel). As I level for cruise and the prop unloads, I dial in more pitch. Bring the pitch back to neutral coming back into the pattern. Works well and zero problems to date.
     
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  7. Aug 20, 2019 #7

    MadProfessor8138

    MadProfessor8138

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    What engine are you running with your inflight adjustable ?

    Kevin
     
  8. Aug 20, 2019 #8

    rv6ejguy

    rv6ejguy

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    Turbocharged Subaru EJ22.
     
  9. Aug 21, 2019 #9

    MadProfessor8138

    MadProfessor8138

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    That's good to know.....
    I heard that Ivo was having a problem with the pitch motor there for a while.

    I'm thinking a constant speed Ivoprop may be in my future......unless someone knows of a reason not to run it on a Rotax670 with gearbox.

    Kevin
     
  10. Aug 21, 2019 #10

    rv6ejguy

    rv6ejguy

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    The constant speed versions didn't work too well and uses up brushes quickly. I'd avoid that one. I wouldn't use the circuit breaker to judge pitch stops as they recommend either. Hard on the motor and screw drive mechanism. Fit an ammeter as I did, which gives you an idea where the blades are. Cheap, reliable. Neutral pitch is where current is lowest and you draw more current as the blades go finer or coarser.
     
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