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Replacing the coil

Posted: Sun Aug 11, 2019 9:11 am
by jfarr
My brother-in-law took umbrage at the dirty appearance of the '74s engine bay at a picnic yesterday, so he got out some degreaser and a hose and went to town. Man alive, that stuff did an amazing job and it's probably something I should have done a long time ago. But when he was done and everything was mostly dry, the car wouldn't start. It would crank but would not fire.

We looked around in there and noticed that the coil was arcing from one post to the body of the coil. We cleaned it off dried it out thoroughly but it still seemed to misbehave a bit. So I'm guessing I need to replace it.

The car was upgraded to electronic ignition by Al before I bought it so I have the Marelli coil mounted to a big heatsink with the ignition module behind it. Looking in the manual, I see that I ought to be running a 3 ohm coil per the service manual. Does anybody have a favorite? A quick search here mentions the Pertronix Flamethrowers but just wanting to confirm.

Re: Replacing the coil

Posted: Sun Aug 11, 2019 1:07 pm
by bartigue
Original Marelli: ... m-original

Bosch 0 221 030 119 replacement: ... 9-85-bosch

If you're doing it also go ahead and get a new HEI unit:

Personally I think the Petronix stuff is just no-name-brand with their sticker on it.