1979 z28 hei power

Discussion in '1978 - 1981 Specific' started by Bitters, Sep 17, 2020.

  1. Bitters

    Bitters New Member

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    I have a 1979 z28 that I bought in 1998, back when I was a dumb teenager. This car came with a freshly rebuilt 30 over 454, a super t-10 4-speed and a 3.73 posi 10-bolt. Everything a good college car needs. The guy I bought it from, bought it several years before with the 454 already swapped in. He ended up selling it to me for what he owed on the loan he took out to have a local place rebuild the engine. I did at one time find the numbers on the block and I believe it was from 73, but maybe 72. Either way it came with a points distributor.

    Anyway here's the question: between the + battery cable and hei power I have about 100ohms of resistance with the key in run. I have less than 1 with the key in start. Is this normal? Sounds like some points type wiring. Is this a problem? I haven't had any spark problems since I replaced a dead hei module a few years ago. I discovered this because previous owners didn't care about proper connectors and while it seems logical that the fat wire is power and the thin wire is tach i decided it was worth making sure before connecting things and hooking up the battery.

    Thanks
     
  2. Gary S

    Gary S Administrator Lifetime Gold Member

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    A points distributor wants a resister wire between it in the run position and no resistance in the start position.
    HEI wants no resistance in any position so it gets 12 volts all the time.

    The car originally would have HEI so the original car wiring would be correct for an HEI. The engine switch wouldn't matter if it gets an HEI when installed in the '79.
     
  3. Bitters

    Bitters New Member

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    I just wondering if the original car wiring is still there or was a resistor wire added (seems like it). If a resistor wire was added, presumably because the engine-original points distributor came along, am I losing any power or hurting anything by leaving it?
     
  4. Gary S

    Gary S Administrator Lifetime Gold Member

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    If an HEI doesn't get full 12v, it can't put out full voltage spark. A weak spark can cause poor fuel ignition and a poor running engine.
     
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  5. CorkyE

    CorkyE Veteran Member Lifetime Gold Member

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    Sounds like a resistor wire was used, should not be that ohm drop. The 454 could had a points distributor when it was swapped and someone later installed the HEI. Dunno - lot of water under the bridge since then.
     

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