Author Topic: Wiring help needed...  (Read 816 times)

Offline danmc77

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Wiring help needed...
« on: August 28, 2009 - 12:02:10 pm »
Ok guys, I know there are 10 million ignition/ballast resistor questions out there, but after reading them, I still have questions regarding how I have my wiring set up. 

I've started w/ a stock repro engine/charging harness, and have made modifications trying to use as much or the original wires as possible. 

These are the mods/updates I've made:

Late-model internally regulated alternator (obviously eliminated the VR on the bulkhead)
remote "sense" wire to a main "bus" (stater relay stud)
Mallory ignition box
Mallory Unilite dist.

Ok, now let me TRY to explain as best I can, as it relates to the ballast resistor, how it is set up from the factory, versus how I have modified it: 

the stock BR has 2 wires leading to one side - one from the ignition switch(brown), and one leading to the + terminal of the coil (blue).  they are on the same side of the BR.  On the other side of the BR is a wire leading to the "ign" terminal of the stock voltage regulator.

That same "ign" terminal on the VR is joined by a wire directly from the ignition switch (blue).  so there are 2 wires on that terminal.  on the other side of the VR, one green wire leads to the "field" terminal on the alternator.

Ok - here's what I did...

The new alt is internally regulated, so I need to connect an "ign," "sense," and "B+" directly to it.  So, First, from the "ign" terminal of the original VR, I extended the harness so the wires connect to the alternator "ign" terminal.  so basically, it's the blue from the ignition switch, and the wire from one end of the ballast resistor.  I routed a new "sense" wire to the starter relay battery post, and routed a 10gauge wire from the B+ on the alt to that same relay battery post.

ok, now that the alt is hooked up, I now had to focus on the Mallory ignition box...

Basically, the Mallory box hooked to the dist with no problems.  It also has a + and - that go directly to the battery for power, again, no problem there.  It has 2 wires that go to the + and - of the coil, no problem, except that it replaces the original BR wire to the + coil terminal.  Now, where I think I get into an issue is the switched ignition source that needs to be connected to a small red wire from the ignition box.  Basically, what I did was take the original coil + wire of the BR (remember the side of the BR that has 2 wires connected - I'm using the one that went to the coil+) and used that to connect to the red wire of the box and distributor. 

So, questions are:

Does this system work the way I have it wired; maintaining the ballast resistor?

If I have to eliminate the resistor, can I just basically connect the wires at either end of the BR, and will that have any effect on the VR in the Alt; since the stock "ign" terminal of the VR came from the BR, is there something to that?

I hope I've explained it clearly - thanks for the help guys!! 



« Last Edit: August 28, 2009 - 12:04:41 pm by danmc77 »
68 Charger
73 Cuda
69 Superbee
71 Demon




Offline danmc77

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Re: Wiring help needed...
« Reply #1 on: August 28, 2009 - 12:03:13 pm »
BTW, it a 68 Charger - but I figure they're set up the same as the e-bodies.
68 Charger
73 Cuda
69 Superbee
71 Demon

Offline danmc77

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Re: Wiring help needed...
« Reply #2 on: August 28, 2009 - 12:28:30 pm »
Ok - I'm pretty sure I know what I have to do, but I just need confirmation from people who know...

I think I just need to get rid of the BR, and keep the 2 wires on the one side connected, so essentially, I'll have the blue wire from the ignition switch continue through the coil wire to the Mallory switched ignition wire. Then I can eliminate the wire from the other side of the BR that connected to the VR "ign" - that NOW connects to the alt "ign." I can do that becaus ethe alt "ign" already has the other wire connected to it directly from the ignition switch as well. Right?

My only concern or question is if, for some reason, the BR was needed for the "ign" side of the VR - now the "ign" terminal of the alt.
68 Charger
73 Cuda
69 Superbee
71 Demon

Offline BruteForce

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Re: Wiring help needed...
« Reply #3 on: August 28, 2009 - 04:48:29 pm »
The ballast resistor has two functions: 1) reduce the voltage to the coil 2) reduce the voltage to other things powered by ignition when starting (so more power goes to the starting). I have an MSD 6AL which sounds like it hooks up the same. The MSD box does not require a ballast resistor for function (1). I just got rid of the ballast resistor and replaced it with a binding post (homemade from an electrical J-box) :stirpot:. To that binding post I ran both ignition and ignition start wires that come from the bulkhead connector, and then everything else powered by the ignition (voltage regulator, alternator, MSD ignition input, fuel pump relay, idiot light, etc.).

I decided not to worry about function (2) of the ballast resistor :misbehaving:.

I don't know anything about the one wire alternators.

Offline Chryco Psycho

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Re: Wiring help needed...
« Reply #4 on: August 28, 2009 - 08:28:09 pm »
what you need to do is connect the + & - from the mallory box to the coil , it will fire the coil & does not require the ballast anymore , the next step is to connthe smalller red switched ign wire to Both the blue 12 v switched wire & the ballast & connect it also to the brown wire at the ballast  to turn the ign on while cranking the engine over

Challenger - You`ll wish You Hadn`t

Offline danmc77

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Re: Wiring help needed...
« Reply #5 on: August 28, 2009 - 10:47:04 pm »
Thanks guys!
68 Charger
73 Cuda
69 Superbee
71 Demon