Coil Meltdown
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Melting Slicks
Joined: Jul 2010
Posts: 2,762
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From: SUFFIELD CT USA 2023 C8 CORVETTE UN-MODIFIED FINALIST
2023 C8 of the Year Finalist - Unmodified
Coil Meltdown
My buddy put a 383 stroker in his '74 just before I did my '77. He was seeing oil droplets on top ? Of his motor? Then his flamethrower coil did a major Chernobyl and he thought that's where the drops came from. The coil was leftover from his points setup. He dropped in the new coil that came with his new HEI distributor on, and the car runs well again. The meltdown was about 1000 miles after the new distributor. Was it just a coincidence or should he not have run the older coil?
Last edited by BPHORSEGUY; May 6, 2020 at 07:30 PM.
Burning Brakes
Joined: Dec 2008
Posts: 971
Likes: 45
From: Middlesex NJ
How is the coil + wire configured? Is it 12v or is it using the resistor wire to drop to around 7 - 8v or so?
Maybe the old coil was simply damaged or the ignition coil wire was changed to be 12 v and was run on a coil meant to only have 7 - 8v?
Maybe the old coil was simply damaged or the ignition coil wire was changed to be 12 v and was run on a coil meant to only have 7 - 8v?
Tech Contributor
Joined: Jun 2004
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From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
My buddy put a 383 stroker in his '74 just before I did my '77. He was seeing oil droplets on top ? Of his motor? Then his flamethrower coil did a major Chernobyl and he thought that's where the drops came from. The coil was leftover from his points setup. He dropped the new coil that came with his new HEI distributor on, and the car runs well again. The meltdown was about 1000 miles from the new distributor. Was it just a coincidence or should he not have run the older coil?
Thread Starter
Melting Slicks
Joined: Jul 2010
Posts: 2,762
Likes: 820
From: SUFFIELD CT USA 2023 C8 CORVETTE UN-MODIFIED FINALIST
2023 C8 of the Year Finalist - Unmodified
I can't answer that without asking him but thank you for your response!
Le Mans Master
Joined: Dec 2006
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There is no such thing as an 8 volt coil.
Le Mans Master
Joined: May 2007
Posts: 5,025
Likes: 1,120
From: North tonawanda NY
yeah the HEI distributor comes with an electricic coil located under the distributor cap so either Your friend did something wrong or your understanding of what he told you is incorrect, as others mentioned the old points coil would have had run off the resistor wire and is not designed to work with HEI also you might want to make sure your friend is not trying to run the HEI distributor off of the 12v resistor wire that the old points system ran off because even though it will work for a short time it will cause failure and leave him stranded. I almost made the same mistake myself until I discovered here that its a No No.
Edit I have a 74 also
Edit I have a 74 also
Last edited by augiedoggy; May 7, 2020 at 10:16 AM.
Thread Starter
Melting Slicks
Joined: Jul 2010
Posts: 2,762
Likes: 820
From: SUFFIELD CT USA 2023 C8 CORVETTE UN-MODIFIED FINALIST
2023 C8 of the Year Finalist - Unmodified
Sorry for any confusion but it is my buddies 74 original points car not my 77 original HEI car. Both were recently changed to 383 strokers! My buddy ran the old points style coil to his new HEI
It does not have the built in coil. His old coil did a meltdown inside of 1000 miles. He replaced it with the new coil that came with the HEI run off a 12v non resistor wire. I guess the question has been answered that he shouldn't have run the old coil. He did so because he was having issues at the time of 383 engine swap almost as a diagnostic tool.
It does not have the built in coil. His old coil did a meltdown inside of 1000 miles. He replaced it with the new coil that came with the HEI run off a 12v non resistor wire. I guess the question has been answered that he shouldn't have run the old coil. He did so because he was having issues at the time of 383 engine swap almost as a diagnostic tool.
Last edited by BPHORSEGUY; May 7, 2020 at 08:49 AM.
Burning Brakes
Joined: Dec 2008
Posts: 971
Likes: 45
From: Middlesex NJ
Big2Bird is absolutely right on this.....
There are 12v and (6v coils). The voltage you should see at the coil wire on a 74 is 7-8v on a the resistor wire .
The resistor wire is meant to protect the points NOT the coil. But if you run HEI or an electtronic conversion kit you should use a non resistor wire and see 12v to the coil.
Running HEI or pertronix etc wont work well with a resistor wire to the coil.
There are 12v and (6v coils). The voltage you should see at the coil wire on a 74 is 7-8v on a the resistor wire .
The resistor wire is meant to protect the points NOT the coil. But if you run HEI or an electtronic conversion kit you should use a non resistor wire and see 12v to the coil.
Running HEI or pertronix etc wont work well with a resistor wire to the coil.
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Coil
Big2Bird is absolutely right on this.....
There are 12v and (6v coils). The voltage you should see at the coil wire on a 74 is 7-8v on a the resistor wire .
The resistor wire is meant to protect the points NOT the coil. But if you run HEI or an electtronic conversion kit you should use a non resistor wire and see 12v to the coil.
Running HEI or pertronix etc wont work well with a resistor wire to the coil.
There are 12v and (6v coils). The voltage you should see at the coil wire on a 74 is 7-8v on a the resistor wire .
The resistor wire is meant to protect the points NOT the coil. But if you run HEI or an electtronic conversion kit you should use a non resistor wire and see 12v to the coil.
Running HEI or pertronix etc wont work well with a resistor wire to the coil.
