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Thread: 4.3 gm dist

  1. #1
    Carb and Points!
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    4.3 gm dist

    Will a 4.3 small cap dist fire when turning counter clock wise ?

  2. #2
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    It may fire but there could be problems with ignition timing. If you want to run the distributor backward you should reverse the pickup coil wires (white and green) on the module.

  3. #3
    Fuel Injected! phonedawgz's Avatar
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    Yes it will fire. No, since it is a distributor, you do not have to worry about timing being off since the timing is set with a timing light and turning the distributor. I also would not reverse the wires of the pick up coil. You want the timing to fire on the rise of the voltage caused by the rotor/stator lining up independent of the direction of the rotation of the distributor.

  4. #4
    RIP EagleMark's Avatar
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    But the rotor/stator/reluctor in this case is same shape both ways. Problem of reverse direction of distributor shaft is timing is also reverse if wires are not swaped.

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  5. #5
    Fuel Injected! phonedawgz's Avatar
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    Not sure exactly what you are saying. I make an assumption that if you are for whatever reversing the direction of the distributor, that also includes setting the timing with a light.

    So for my interest, I grabbed a 4.3 distributor and my digital scope and looked at the wave form. I get the same wave form - a positive slope to a spike that immediately goes negative and then slopes back to zero. The waveform looks like this (not my pic, and not from my dist)Mgd2.jpg

    The interesting thing is the wave form has the same polarity if I turn the rotor clockwise or counter clockwise.

    I am reading the voltage using the white wire as reference, and fwiw this is a 4.3 star style (not points and prongs) type pick up.

  6. #6
    Fuel Injected! JeepsAndGuns's Avatar
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    I know when I first did my conversion and was trying to get it running right, I had originally had the pickup coil wires reversed. It started and ran (although like poop) but I was able to set the base timing just fine. Once I found out the reversed wires I swapped them and had to reset the base timing. I cant remember how much it was off (it was so long ago) I just remember it was off by a few degrees. It did work and run, but the running like poop ended up being something different.
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  7. #7
    RIP EagleMark's Avatar
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    Right, not that the signal is differant either way, but something to do with the signal into EST changes timing. Same thing happens with duraspark to external EST module in a conversion. So it's not the signal, it's signal going into EST.

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  8. #8
    Carb and Points!
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    I beleave what your saying is it may retard instead of advance timing if I don't reverse wires.

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