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Flatthead build up, detail question - VALVE GUIDES

Discussion in 'The Hokey Ass Message Board' started by AV8-Rider, Jan 12, 2005.

  1. AV8-Rider
    Joined: Jan 31, 2002
    Posts: 909

    AV8-Rider
    Member

    I have a nother little detail puzzling my mind these days, planning the assembly of my Flattie.

    I bought this block from an oldtimer who had spent A LOT of hours porting channels
    The valve guides are later solid 8BA's with the rubberseal on the intakes.
    The man has made the guides a part of eatch port job, making very smooth channles from valves and out.

    I dissasembled the guides before boiling out the block. some of them where quite loose, others needed some knocking.

    Here the puzzle: How shall I fix them when asembling. I want the guide to stay in place since everyone is an individual and a part of the smoothness. How likely are they to rotate after some running.

    I have thought of any kind of locktite or similar products. Another idea is to drill in a latch pin partly in guide and partly in the block.

    ANY OF YOU SCILLED DUDES HAVE ANY EXPERIENCE WITH THIS???? [​IMG]

    The block before boiling etc.

    Paul
     

    Attached Files:

  2. AV8-Rider
    Joined: Jan 31, 2002
    Posts: 909

    AV8-Rider
    Member

    One of 'em guides
     

    Attached Files:

  3. alchemy
    Joined: Sep 27, 2002
    Posts: 17,441

    alchemy
    ALLIANCE MEMBER

    Knurl 'em, install them bare, and pretend they are part of the block. It will make installation of the valve and spring tougher, but you will not have the guides moving around on you.

    I think most guys (99.99%) don't shape the guides like yours. But I can see how it might help breathing. Or maybe it's just overkill.

     
  4. Bruce Lancaster
    Joined: Oct 9, 2001
    Posts: 21,682

    Bruce Lancaster
    Member Emeritus

    And before knurling them, scribe a line on top and onto block, then from line on top straight down side of guide so you can accurately align them as you install. The traditional common way of cutting the guides is/was to turn them in a lathe to a slope like part of yours, but symmetrical. Shaping the port bowl floor is interesting and little discussed...Flatdog???.
    In the HRM writeup on Bingelli's ridiculously fast gasser many years ago, they reported he actually poured lead into that area to allow some shaping presumably ABOVE the stock floor--but the article gave no details or pics of this--does AV8 know anything about this???
     

  5. Elmo Rodge
    Joined: May 12, 2002
    Posts: 2,339

    Elmo Rodge
    Member

    Bruce, when we were talking the other night about filling the ports I was going to mention that I had considered molding lead in there but, got distracted. Wayno
    p.s;check your PMs
     
  6. Kilroy
    Joined: Aug 2, 2001
    Posts: 3,225

    Kilroy
    Member
    from Orange, Ca

    [ QUOTE ]
    In the HRM writeup on Bingelli's ridiculously fast gasser many years ago, they reported he actually poured lead into that area to allow some shaping presumably ABOVE the stock floor

    [/ QUOTE ]

    Wouldn't this also be a way to reduce the inside area of the port and thus speed up the mixture as it travels through? I think one of the main problems of the stock port is that it kind of "opens up" in the center causing a slight back-water effect and possibly allowing the fuel to fall out of suspension.

    Also the flow data I've seen, seems to indicate that the bottom of the port doesn't effect flow that much for normal street driven engines at normal speeds, with the usual gas.

    All that said I sure was tempted to go after the floors and guides on mine when I was porting it! It is just too tempting when you've got a grinder in your hands and are staring at a rough surface! [​IMG] [​IMG]

    Oh yeah, I think the knurl/scribe method sounds like a good bet to me. After that do you JB-Weld the guides in place?

    Also could someone describe how guides are knurled?
     
  7. Flat Ernie
    Joined: Jun 5, 2002
    Posts: 8,406

    Flat Ernie
    Tech Editor

    Related only because it's a flathead - how's this for some radical machining?

    Anyone know anything about this? It was posted on the Harley site - Flatheadpower...


    [​IMG]
     

    Attached Files:

  8. Digger_Dave
    Joined: Apr 10, 2001
    Posts: 2,517

    Digger_Dave
    Member

    [ QUOTE ]
    Also could someone describe how guides are knurled?

    [/ QUOTE ]

    For the outside of the guide (body) a knurling tool. The tool is held in a lathe tool post and brought to bear against the guide. (the wheels on the knurling tool are hardened and "upset" the surface; also making it larger in diameter)
     
  9. Digger_Dave
    Joined: Apr 10, 2001
    Posts: 2,517

    Digger_Dave
    Member

    It's strange. This thread reminds me of a saying that a guy once "coined." It seems to fit here.

    Question: So why would you go to that much work for a technology that's over 70 YEARS OLD!

    Answer: "To see if I can squeeze the last "POOFTEENTH" out of it!
    - carps
     
  10. 296 V8
    Joined: Sep 17, 2003
    Posts: 4,666

    296 V8
    BANNED
    from Nor~Cal

    Flatfire’s block?
     
  11. av8
    Joined: Mar 3, 2001
    Posts: 1,716

    av8
    Member

    [ QUOTE ]
    . . .In the HRM writeup on Bingelli's ridiculously fast gasser many years ago, they reported he actually poured lead into that area to allow some shaping presumably ABOVE the stock floor--but the article gave no details or pics of this--does AV8 know anything about this???

    [/ QUOTE ]

    Yes, av8 does. Bing's approach amounts to straightening the intake tract as much as possible. Years ago he added filler to the bottom of the runner between the intake deck and the guide, as well as the bottom of the bowl past the guide. He found that the filler in the beginning of the tract was more work than it was worth, but still adds filler to the bottom of the intake bowls to provide a "ramp." Today he uses a Devcon-like epoxy filler rather than lead . . . easy to shape with fingers while it's still "plastic" -- and not as painful. [​IMG]
     
  12. AV8-Rider
    Joined: Jan 31, 2002
    Posts: 909

    AV8-Rider
    Member

    Hi and thanks a lot for info and tips guys.

    HAMB's been spooky the last days. I posted a reply here on this post yesterday, and it dissapered. Saw there where apost by Zodoff aswell that are gone.
    nice that things are new and QUICK now.

    I'll look aout for a knurl-tool. looks to be the way to go. Anyway I will fix them in a more or less permanent way. Not likely that they are going out in my lifetime. [​IMG]

    Paul
     
  13. Flatdog
    Joined: Jan 31, 2003
    Posts: 1,285

    Flatdog
    Member Emeritus

    Loose guides?,use a oversize one and ream block to fit.your intake should be turned a round taper in a latht.Locking valve guides in the block will make you crazy when you try to assemble it.Exh guide realy dont need a lot of work just a mild doming on top.I am reluctant to tell you aboub porting not much room for error.read hollerman book and davis stuff too.READ READ Av8 stuff is also top noth also.
     
  14. pigpen
    Joined: Aug 30, 2004
    Posts: 1,624

    pigpen
    Member
    from TX USA

    [ QUOTE ]
    Knurl 'em, install them bare, and pretend they are part of the block. It will make installation of the valve and spring tougher, but you will not have the guides moving around on you.

    I think most guys (99.99%) don't shape the guides like yours. But I can see how it might help breathing. Or maybe it's just overkill.



    [/ QUOTE ]

    The guides are supposed to move in and out. When you install the retainer clips you use the special pry tool to pull them down agianst the spring pressure; they should slide. No lead, no JB weld, no knurling, just assembly lube. The experts recommend using the rubber seals on both intake and exaust. Get a new set of guides that havent been tampered with, and some new rubber seals. The guides you have may wobble in the hole. Franl Oddo's book is a wealth of info.

    pigpen
     

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