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Duraspark wiring

Teal68

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Yea, another dumb electrical question from Tyler.....

I've wired a Duraspark ignition into my 68. It works fine, but I'm curious since the white wire goes to I on the solenoid can I remove the old wire from the I terminal?

As usual...Thanks!
Tyler
 

DirtDonk

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You could, but I'm not sure I would. The ignition would still work without either wire on the I post in fact, but both serve a different function.

The original Brown wire still gives an additional punch to the ignition coil only.
The White wire sends a "start" signal to the module to do whatever it does with that information. I ran my module without a White wire for many years and probably would never have noticed a difference either way.

One of the others can tell you what it's function is. Viper might know, but I believe most of the members here that know such things say that the blue grommet modules (presumably that's what you're using?) do not have a start-retard function to aid in starting (especially when hot) but maybe they have a feature that increases, or decreases spark dwell time or something like that.
I don't know, but it will run fine without it.

And the same goes for the Brown wire actually. With your much better ignition the extra 12v jumper when starting is not as critical with a well tuned and good running engine.
But Ford left it there through the whole early Dura Spark years, so not really any big reason to remove it either.

You just trying to clean up the wiring? Or having some other issue?

Paul
 

DirtDonk

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I should add that if you have changed your ignition coil to one that does not require a resistor wire, then you no longer need the Brown wire.
However, I don't know if a standard Dura Spark box likes controlling a 12v coil or not. Here again, maybe the others know about that kind of stuff.

Paul
 

joshd1971bronco

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Oklahoma City, OK
JUST yesterday I fired up my truck for the first time after DirtDonk helped me through my duraspark wiring. Here's what I have (colors based on blue grommet module and factory wiring):
White wire = 'S' terminal on the solenoid
Red wire = keyed 12v
Green w yellow dashes = negative terminal on coil
The other three wires from the factory connector go to the distributor connector.
Also, I have a pair of wires going to a factory connector (one green, one black with green dashes) that is NOT USED.

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1f4d38257e9216eb7de938480e17c862.jpg
 

ntsqd

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Upper SoKA
Ran an E-Core coil with a blue strain relief module for about a decade on my then DD '67 Ranchero. Both were JY sourced, never had an issue.
 
OP
OP
Teal68

Teal68

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You just trying to clean up the wiring? Or having some other issue?

Paul

That's correct Paul. Trying to get rid of wires if possible. As it is now I would have to splice into the existing wire at the I terminal, or convert both wires to ring terminals to be able to connect to the solenoid.
 

Skytrooper15

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Sep 13, 2018
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Tuscaloosa,Al
From what I have read about the duraspark ignition system the brown wire sends a signal to the module to retard the timing only during start.That really helps a high compression engine as well as a stock engine giving you a faster start.
 
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