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Discussion Starter #1
So I fired up the new 331 for the first time. Starts up and sounds pretty good (no exhaust just open headers). Keeping the revs up for the cam break in and what do I spy as I peer between the hood & cowl but a little smoke. Probably just a little spilt oil I figure so no big worry. Keeping a foot on the gas, I peer out the door & around the windshield and hood. Yikes its the wiring harness smoking as it melts :: . The red wire from the firewall to the starer relay (same post as the positive battery cable) got so hot it totally melted the entire harness. The battery cables were also very hot (but no melting of insulation). I was so unhappy I haven't done any further investigation yet. So the questions are:
1) Does sound like a bad ground?
2) Is the red wire (new repro harness, not sure what original color is) for the fuseblock and/or headlights?
 

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On my 66 that runs though the amp meter to the alternator. I'd guess that's the main charge line and the voltage regulator is at falt. Good thing you didn't smoke your 331. Chuck
 

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i take it you were doing this with shorty headers? If so.... you had it coming ;)

Sorry to hear about the mess, just splice in new wire and rewrap and it will be good as new (just make sure you replace ALL that needs to be replaced, electrical demons are the worst)
 

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Discussion Starter #4
Actually it was long tube headers, but it was not melting from the heat of the headers. The wires were heating up from the current flowing through them, so unfortunately its not a simple as your solution, that would just result in same thing or worse ::. Yep, electrical demons suck :(
 

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Discussion Starter #5
Hmm, that sound reasonable, I'll check the regulator (although mine is a 65 , it also has the gauges with the ammeter). Thanks.
 

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I'd suspect that that red line has a short somewhere, probably at the dash (ammeter). Don't ask how I know! It is not fused.
 

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Discussion Starter #7
Does that loop back to the regulator or alternator? I'm looking an easy way to quickly verify whether or not I have continuity along that line.
 
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