76 (?) Engine Wire Harness

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Mar 9, 2008 | 08:24 PM

dgrant09

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76 (?) Engine Wire Harness

We are beginning a Duraspark conversion on our '72 F250, 390. The engine wire harness is supposed to be a 76. There is a wire lead coming off of the coil connector that is red and maybe a brown stripe. This lead is about 3" long and has a female spade type connector on the end.
Would anyone know what this tap is for? On some schematics I see a noise filter, but that is off of the other side of the coil with a green wire..
Thank you

Mar 10, 2008 | 07:22 AM

fmc400

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From: Austin, TX

If it's on the "switched ground" side of the coil (the terminal that makes its way back to the Duraspark box), then it's probably for a tachometer. If it's on the "hot" side of the coil (the terminal that makes its way back to the resistor wire downstream of the dash wiring) then it's probably for the noise filter.

Mar 10, 2008 | 09:20 AM

Franklin2

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This schematic does show a noise filter on the + side of the coil. Be careful though, these schematics are full of errors. But you can probably believe that part of it.

http://www.autozone.com/images/cds/g...3d800ce986.gif

Mar 10, 2008 | 01:42 PM

dgrant09

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Quote:

Originally Posted by Franklin2

This schematic does show a noise filter on the + side of the coil. Be careful though, these schematics are full of errors. But you can probably believe that part of it

Thank you. We were looking at those also and from the wire colors I thought the filter was on the tach side. An old timer at the local Ford dealer sides with you. We'll leave it off unless we have a static issue over the radio. If that happens, we'll pick up a condensor..
Thank you!!