First Pitts owner - air filter intake mod - help!

Discussion in 'Pitts Fuselage & Empennage' started by 3dbuster, Apr 8, 2018.

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  1. Apr 8, 2018 #1

    3dbuster

    3dbuster

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    Hi Pitts drivers!

    Recently I purchased a used S1S Pitts with two close friends, the Pitts was built early 2000 and was mainly flown in competitions.

    We are keen to modify the direct air intake/stack to facilitate an air filter to improve the longevity of the engine, as I am new to this - I would love to know what you guys did for air filter and if you recommended any specific mod we can get to reduce the conversion work time?


    Many thanks!

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  2. Apr 8, 2018 #2

    DrunkenWoodpecker

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    It's a boy!
     
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  3. Apr 8, 2018 #3

    Chris McMillin

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    The only thing wrong with that airplane is it doesn't have a prop on it. Go fly it.
    Chris...
     
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  4. Apr 8, 2018 #4

    3dbuster

    3dbuster

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    Perhaps it’s important to note the airplane will be flown regularly from a gravel strip
     
  5. Apr 8, 2018 #5

    race38

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    PJ Motorsports sells velocity stack screens that could be used on the intake “probe”. About $35. pjmotorsports.com
     
  6. Apr 8, 2018 #6

    PittsDriver68

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    Factory airplanes have no air filter, just hardware store screen to keep the larger rocks and birds out.

    I do 15 hour oil changes to keep the engine internals clean. The last overhaul was at 1200 engine hours.

    Best of luck,

    Wes
     
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  7. Apr 8, 2018 #7

    TFF1

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    I will want to hear how it does on yaw situations. I think it would
    Start choking the engine. You need one of the Mooney style intakes.
     
  8. Apr 8, 2018 #8

    cwilliamrose

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    My S-2A has a 2" Bracket air filter element placed in the cavity between the factory screens and the servo. The element is customized to fit and there's another screen behind the element to keep it in place. The airplane was based in a dry, dusty environment so I can see the need for this addition. I'm not sure it's required in SW Florida where insects are the more common ingestees. Other than the extra stuff (the element plus the extra screen) in the intake path I see no reason to change what was done.
     
  9. Apr 9, 2018 #9

    Larry Lyons

    Larry Lyons

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    I see a lot of work here to make the changes your looking at including a new lower cowl. The velocity stack mentioned in post 5 will be, by far the easiest and quickest too.
     
  10. Apr 9, 2018 #10

    PittsDriver68

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    "My S-2A has a 2" Bracket air filter element"

    Interesting mod. Brackett air filters were invented for dusty environments.

    The stock screen does stop the bugs but I notice that looking down into the fuel control there is a lot of dirt buildup. With the Bracket element in front, does it keep the fuel control clean?

    Take it out and I will think that you gain and inch of MP.

    Best of luck,

    Wes
     
  11. Apr 10, 2018 #11

    3dbuster

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    Thanks for all the reply guys.

    The solution from PJ Motorsports will fit perfectly to our needs. I will organize few to be sent to us.


    As for the questions regarding airflow disturbance on high alpha/knife edge - the airplane is flown regularly since 2001 with no signs of an issue with air/fuel ration or any engine misbehave.

    Will post some pictures after we get the velocity stack filters from PJ.


    Thanks again! :)
     
  12. Apr 11, 2018 #12

    cwilliamrose

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    I can't easily get to the intake with the nose bowl in place but looking through the backing screen didn't reveal any great amount of crud stuck to the walls. If I get better access I'll report back.

    I'm sure all that extra stuff in the intake passage is worth an inch or so of MP.
     
  13. Apr 11, 2018 #13

    ndlakesdreamer

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    Brackett air filters have oil impregnated in the element. It's common to have that oil blow back into the injector body. The only place it concerns me is when it's in the four small tubes that are used for air volume sensing. Conversations I've had with injector repair facilities indicates it happens all the time.
     
  14. Jun 12, 2018 #14

    3dbuster

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    Hi Guys,

    Few months and the little girl got back to the air on Friday, I ended ordering a filter from Bill at PJ Motorsports. Bill was kind to make a custom size to fit nice and snug on the intake. Very happy with this and feel slightly better going to our gravel strip..

    Thank you kindly!
     

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