Author Topic: resistance wire install  (Read 678 times)

shelbydoug

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resistance wire install
« on: July 31, 2020, 07:32:38 PM »
This is the reistance wire I bought. It has male bullet connectors at both ends.

It is obvious that one end will just plug into the bullet connector on the tach output.

Why is there a bullet connector on the coil end? Is there an adapter to use on the coil?

Which end goes on the tach?
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The Going Thing

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Re: resistance wire install
« Reply #1 on: July 31, 2020, 07:58:49 PM »
Doug: When you take the fire-retardant wrap off you'll find the other end.

shelbydoug

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Re: resistance wire install
« Reply #2 on: July 31, 2020, 08:47:54 PM »
There are male bullets on both ends. You take the insulation off? Why?
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The Going Thing

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Re: resistance wire install
« Reply #3 on: August 01, 2020, 01:47:09 AM »
I think my 67 was enclosed, I don't remember it being outside the wrapping of the harness.  I could be wrong in this case.

shelbydoug

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Re: resistance wire install
« Reply #4 on: August 01, 2020, 06:59:41 AM »
What does the pigtail to the coil look like? I can't find that anywhere.
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Coralsnake

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Re: resistance wire install
« Reply #5 on: August 01, 2020, 07:36:19 AM »
Doug, what are you trying to accomplish?

I dont think the Ford tach takes its signal directly from the coil.
« Last Edit: August 01, 2020, 08:01:48 AM by Coralsnake »
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Royce Peterson

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Re: resistance wire install
« Reply #6 on: August 01, 2020, 08:28:16 AM »
The wire at the firewall end of the existing harness must be cut as close to the firewall as possible. An insulated female connector must be crimped on to accept the Ford resistance wire repair kit.

The tachometer in this car is a current sensing unit. In order to be accurate it needs to see 12 volts input from the ignition switch and then the resistance wire and coil on the other side. The coil needs to be either an original yellow top or another coil with the same resistance so that current is the same as stock.

Yes the tachometer gets it's signal directly from the coil.

Doug, what are you trying to accomplish?

I dont think the Ford tach takes its signal directly from the coil.
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Darrpo

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Re: resistance wire install
« Reply #8 on: August 01, 2020, 09:02:37 AM »
If you want an orginal style connector check with Mike Williams with Orlando Mustang. He had custom molds made for doing this.

shelbydoug

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Re: resistance wire install
« Reply #9 on: August 01, 2020, 09:56:49 AM »
Doug, what are you trying to accomplish?

I dont think the Ford tach takes its signal directly from the coil.

Generally...getting the tach to work right with a Petronix ignior.

Getting specific information from others is dental surgery...pulling teeth.

Key details are always emmitted.


At the moment, I am down to connecting the resistance wire to the coil. I don't remember specifically what the pigtail on that wire to the coil + terminal looked like.

IF this service part is the same as production line then there is a pigtail required to connect to the coil? Maybe it's different then production?


I'm thinking it was a white wire with a molded female bullet on one end and a 90 molded push on post terminal on the other? I don't have any pictures of that detail.

The Ford Service part has male bullet ends at either end. One is very thick. One thin. I think the thin one goes to the tach output?

I think the fat one connects to the coil pigtail and just lays on the intake manifold?


Hearing from several here running a similar set up, the wiring plan of leaving the resistance wire in place from the tach to the coil, and running a seperate ignition switched 12v wire to the coil holds the most hope of success.

My original resistance wire was cut out years ago, so I'm rewiring from scratch, so to speak.

Again, what does that coil end pigtail look like? Anyone have a picture?


I do remember the discussion Pete habout the replacement yellow top coils vaguely since I wasn't running that set up but is a consideration right now.

A high likeliness of a melted coil is not a big selling point but that coil just came up in a Google search this morning and refreshed my memory a little with blurry details?


Hey. It's the same for me as it was eons ago. If I had instant technical recall, I could have been smart? Sometimes I misspell my own name? NOT a big plus on my part.



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Royce Peterson

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Re: resistance wire install
« Reply #10 on: August 01, 2020, 10:19:26 AM »
The kit that you bought is a repair part that can be used on any Ford product. It requires that the wire to the coil be cut at the interior side firewall. Then install an insulated female connector. Then plug it in.

 It's really simple to do.
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shelbydoug

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Re: resistance wire install
« Reply #11 on: August 01, 2020, 11:02:07 AM »
The kit that you bought is a repair part that can be used on any Ford product. It requires that the wire to the coil be cut at the interior side firewall. Then install an insulated female connector. Then plug it in.

 It's really simple to do.

thank you Royce. The tach end is not the question, the coil end is. If I was going to cut and splice I would have gone to a universal part and saved the effort.

If the answer is to cut the bullet ends off and crip an eyelet onto the wire, it kind of defeats the effort?
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KR Convertible

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Re: resistance wire install
« Reply #12 on: August 01, 2020, 11:20:37 AM »
The resistance wire doesn't continue past the firewall connector.  The engine harness is regular wire.

Royce Peterson

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Re: resistance wire install
« Reply #13 on: August 01, 2020, 12:07:37 PM »
Exactly right. Here's what the factory harness looks like. Note that the Resistance wire is the pink wire that goes from the tachometer to the neutral safety switch harness at the firewall. It is identified as a squiggly line on wire #16A. You will be able to easily tell where the resistance wire is spliced to regular wire. That's where the connector goes.


The resistance wire doesn't continue past the firewall connector.  The engine harness is regular wire.
« Last Edit: August 02, 2020, 11:13:55 AM by Royce Peterson »
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The Going Thing

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Re: resistance wire install
« Reply #14 on: August 01, 2020, 01:25:15 PM »
You can wire the Pertronix without any cutting or splicing. A simple scotch lok on the right side (Ign side) of the harness where it's plugged into the tach. Pull a 14ga wire through the engine harness boot  at the firewall and run it parallel with the existing engine harness under the clips on the valve cover. butt splice it to the red wire from  the Pertronix module to the wire you just pulled. The ford wiring and the black wire go on the coil as it did from Ford.
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