Orfice in the pump cavity

Discussion in 'The "Juice Box"' started by Gary Bohannon, Jan 10, 2020.

  1. Gary Bohannon

    Gary Bohannon Well-Known Member

    A 1970 case does not have this orifice. my 66-67 case does. Should I remove this orifice with a tiny pin hole in the center? Located about 1-2 inches left from the bottom center of the case looking into the bell housing.
    Need to know, please.

    I think it is switch pitch related and I no longer have a switch pitch. Hope it does not interfere with fluid flow on a fixed stator setup.
     
    Last edited: Jan 10, 2020
  2. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    That sounds like it is for a switch pitch. One of the case holes gets plugged and it has a small hole. I think I remember guys using the end of a glass fuse for a plug when converting to SP.
     
  3. Jim Weise

    Jim Weise EFI/DIS 482

    no issue Gary... GM actually deleted that whole area of the casting in later years. Only required for VP operation.

    JW
     
  4. Gary Bohannon

    Gary Bohannon Well-Known Member

    Thank you, so I'll just ignore it and install the pump.
     
  5. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    It's the red dot in this picture.

    SwtchPtchCaseHole.jpg
     
  6. Gary Bohannon

    Gary Bohannon Well-Known Member

    That's exactly where the orifice is. Thanks.
    The case tag says 66 BU, but is a 67 and up BBB bolt pattern.
     
    Last edited: Jan 12, 2020
  7. That's because it's probably from a 66 LeSabre or Sport wagon 400.

    upload_2020-1-12_13-3-16.png
     

    Attached Files:

    Last edited by a moderator: Jan 12, 2020
  8. Gary Bohannon

    Gary Bohannon Well-Known Member

    I bet your right. My 66 BU apparently was from a LaSabre which had the st400 tranny and had a 340 engine. Also had the correct bolt pattern to fit the small blocks and the upcoming big block 400-455 engines.
    Thanks guys.
     
    GranSportSedan likes this.

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