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Really confused now

Discussion in 'Early CJ5 and CJ6 Tech' started by sparky, Mar 4, 2006.

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  1. Mar 4, 2006
    sparky

    sparky Sandgroper Staff Member Founder

    Perth, WA
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    Could be.

    We're saying the same thing here.
     
    sparky, Mar 4, 2006
    #21
  2. Mar 4, 2006
    Patrick

    Patrick Super Moderator Staff Member

    Los Alamos, NM
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    AFAIK, the module is the same be it EF or OF. The distributer shaft/ pickup coil are what triggers the ignition for the different angles on the OF..
     
    Patrick, Mar 4, 2006
    #22
  3. Mar 4, 2006
    Patrick

    Patrick Super Moderator Staff Member

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    Here's an OF pickup on EF dist. See how two os the points line up, but the one between doesn't?
     
    Patrick, Mar 4, 2006
    #23
  4. Mar 4, 2006
    vanguard

    vanguard

    Can't speak to the distributor or the MSD exactly, but when I was inquiring with Mallory. The OF caused problems with the ignition box when a rev limiter was incorporated into the unit. Therefore the standard Hyfire IV w/o the rev limiter worked with the OF, but the pricier units with the rev limiter would not.
     
    vanguard, Mar 4, 2006
    #24
  5. Mar 4, 2006
    timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    Medford Mass USA
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    Patrick has seen more of these than me, but I'd expect that the only way you could get 6 signals from 3 lobes (without adding some electronics) is if there are 2 pickup coils. These could be placed in the distributor at different angles, and would both have to connect to the module. The module would fire when either of them is next to a lobe, not both as Patrick implies from the above picture.

    My theory about a 2x speedup still stands though...
     
    timgr, Mar 4, 2006
    #25
  6. Mar 4, 2006
    Patrick

    Patrick Super Moderator Staff Member

    Los Alamos, NM
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    The pickup coildoes have 6 "points", spaced un evenly. Only three lobes on the dist. tho, (at least on a modified-for OF, EF distributer...
     
    Patrick, Mar 4, 2006
    #26
  7. Mar 4, 2006
    Patrick

    Patrick Super Moderator Staff Member

    Los Alamos, NM
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    I understand that the distributer turns half as fast as the crank, but each cylinder only fires once every other crankshaft rotation....
     
    Patrick, Mar 4, 2006
    #27
  8. Mar 4, 2006
    timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

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    Yes, but if it had spark on every crankshaft rotation, it would not matter? I don't think it would.

    <edit> No, forget that. It's triggering twice as often, but the in-between triggers do nothing since the rotor isn't pointing at a terminal in the cap.

    Having 6 pickup coils unevenly spaced and 3 lobes makes sense now. Thanks Patrick.
     
    timgr, Mar 4, 2006
    #28
  9. Mar 4, 2006
    Patrick

    Patrick Super Moderator Staff Member

    Los Alamos, NM
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    Nope. In fact, for instance, until recently, Harley's V twins fired both plugs at the same time. Just that one plug is firing in a cylinder with nothing to ignite....
     
    Patrick, Mar 4, 2006
    #29
  10. Mar 4, 2006
    Mcruff

    Mcruff Earlycj5 Machinist

    Albertville, AL
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    Harleys are oddfire motors also.;)
     
    Mcruff, Mar 4, 2006
    #30
  11. Mar 4, 2006
    Patrick

    Patrick Super Moderator Staff Member

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    Not sure how a 2 cylinder can be an odd fire. There's an equal amount of degrees between all of the crankshaft throws....
     
    Patrick, Mar 4, 2006
    #31
  12. Mar 4, 2006
    Mcruff

    Mcruff Earlycj5 Machinist

    Albertville, AL
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    Not exactly, thats what gives them ther sound, kinda like the old 2 cylinder John Deeres.
    Thats one of the tings that stopped or slowed the fuel injection setup for Harleys and the aftermarket, its also one of the reason that alot of Harleys are running mega squirt.
     
    Mcruff, Mar 4, 2006
    #32
  13. Mar 4, 2006
    Glenn

    Glenn Kinda grumpy old man Staff Member

    Apopka, Fl
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    Reading all of this makes me realize how much I like my F-heads and flatheads. :D :hurrican:
     
    Glenn, Mar 4, 2006
    #33
  14. Mar 5, 2006
    Warloch

    Warloch Did you say Flattie??? Staff Member

    Falcon, CO
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    I have converted several EF to OF units... I have seen bits and pieces of my understanding on this but thought I would add my $.02...

    You don't 'have' to remove the 'extra' lobes on the distro shaft. They are there to make a magnetic signal via the unevenly spaces lobes on the pickup coil. This tells the module it has signal and fires the coil in the cap which provides juice to the rotor and then it out to the plug it's hitting.

    I have seen this wear out the pickup coil and cause 'some' odd behavior in timing - but not major - at least what I have seen.

    I remove the extra lobes, and you must replace the module, pickup, cap, and I also do the terminator (not sure if it's required). It also helps to change the vaccum advance unit, and I check the weights.
     
    Warloch, Mar 5, 2006
    #34
  15. Mar 5, 2006
    sparky

    sparky Sandgroper Staff Member Founder

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    Ah, thanks. That's what I was trying to ask. :)
     
    sparky, Mar 5, 2006
    #35
  16. Mar 5, 2006
    Patrick

    Patrick Super Moderator Staff Member

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    So, does this mean when I had the EF dist. with the OF pickup, cap, etc., it coulda shoulda worked??? Doesn't really matter now that I've got the Pertronix, etc., but I still wonder..
     
    Patrick, Mar 5, 2006
    #36
  17. Mar 5, 2006
    Warloch

    Warloch Did you say Flattie??? Staff Member

    Falcon, CO
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    Yup - if you changed all the internals out... I have a converted EF as a spare for my OF.
     
    Warloch, Mar 5, 2006
    #37
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