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Harness Modification Questions

MsBeep

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Hi Guys

Since I joined the nest, I have been working away on the Bird, and have a couple of questions regarding the wiring modifications in place, and in progress.
My car is equipped with a 1968 383 HP block (currently has mild MP cam ) A/T (formerly A833 four speed) a Carter 625 AFB carb, manual steering, drum brakes.

Frustrated by the poor quality and tail-light warranty on remanufactured single-point distributors, I added the MSD 6420 6AL box and Blaster 2 coil, and a single-field 60 amp alternator in 1995. A Pertronix Ignitor replaced the points distributor in 2002, and up until my first cable melt in 2009, everything electrical worked well together.

After replacing the voltage regulator, starter relay, and IGN 1 wiring (that melted in the engine compartment harness and to the ignition switch) I believe some mistakes were made at the ballast resistor to MSD trigger wire "hook up". I had another Mopar owner assist me and he, in hindsight, didn't know then what I know now.
The ballast resistor and the original wiring were reconnected in haste and to the best of his knowledge.
The end result: Another cable melt in the same wire; another summer spent in my garage. :brickwall:

Modification #1:
To pass the time in an educational manner, I repaired and renewed the engine wiring harness that was on the car, and even did a trial fit yesterday. :thumbsup:
The reworked harness includes the MSD/Mopar Ignition wiring mod (join IGN 1 blue and IGN 2 brown together and connect to MSD trigger small red wire ) NO ballast resistor
required and no OE + coil wire needed.
I used a three-way connector to splice the three wires together, but have plans of soldering and heat shrinking that modification when I get the new harness. I have been looking for a better way to make this connection- has anyone done this and if so, how did you do it?? Any pictures of this available?

Modification #2:
After reading many articles and posts on the Internet, I thought the popular ammeter by-pass or wiring mod would be a good thing to do. I did the easy part first:
I ran a 10 gauge alternator feed wire with 14 gauge fusible link on the end, from the battery stud on the alternator to the battery stud on the starter relay.
I had to cut the violet wire for the horn relay that was companioned with the original alternator charge wire (at the BAT terminal on the back of the housing) but I expect to have the replacement wire in the new engine harness.
Half done and sitting on the fence:
Option #1:
With a factory style fusible link, from the starter relay to the bulkhead connector terminal J in place; will the red wire that goes to the ammeter "feed" the black ammeter wire
that I moved overtop the red wire terminal on the Red ammeter stud? As I understand it, I have a solid connection that bypasses the AMP gauge AND feeds power via the starter relay connection to the black wire BEFORE the distribution point in the dash harness. Is this right? If so, I can hardly wait to plug in the new harness, connect a new voltage regulator and do the MSD wiring mod.

Option #2:
The oft-referenced MAD electrical method : bypassing bulkhead connector terminals P and J. Since I have minimal heat damage in the bulkhead connector, and new harnesses on order, I would have to pull the female terminals out of the dash harness on the cabin side of the BH for those two wires; cut the terminals off, extend both wires to reach the starter relay area, splice together and add 16 gauge fusible link complete with heat shrink, on the end. I can utilize the former clutch rod hole as the pass-through, and already installed a rubber grommet. Can I leave the ammeter ring terminals as connected, or do I have to splice them together another way?

It has also been a while since I cleaned the bulkhead connections at the firewall under the dash- can anyone tell me what is the best way to release the spring clips that hold the BC in the firewall? I think I can use a flat blade screwdriver on the clips ( engine bay side) and the push it forward into the cabin-will that work?
I would like to be able to get a better look at all the connections - without the neck pain, and run the wires for the second half of the ammeter bypass if "option #1" is not doable.

Anyone with a useful suggestion or the voice of experience please speak up!


Marilyn
aka "MsBeep"
 
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Big John

Sit back, relax Don't bitch about the cigar smoke
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On the connection, solder and heat shrink. It's the best way.

For your Mod#2. You can just run the jumper with fusible wire from the alternator to the starter relay as you have done and leave the rest intact. Everything will work just fine and you won't be running any other wire. You are essentially bypassing the bulkhead for charging the battery.
 

MsBeep

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On the connection, solder and heat shrink. It's the best way.

Yeah, I kinda thought you might say that! Just to clarify: The connection you are referring to is the MSD Trigger to IGN 1 and IGN 2 wires?

AND For Mod #2, my "option 1" is correct and waiting for the new wire/fusible link to be reconnected at the bulkhead??
 

MsBeep

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"Girly-matic" transmission - not by choice Dave. :lol: Unfortunately for me, the four-gear transmission and all hardware was long gone by the time I found this car! :stooges:
 

Basketcase

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just a little background....we tese each other about our cars. color(I'm sure you noticed that already) and how manily the cars are. The wusses have power steering,brakes,etc, and some even have air conditiong. Then there's the rest that have manual steering,brakes,etc, and the best is a four speed. Others have automatics(girlymayics).
 

Jim S.

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On the connection, solder and heat shrink. It's the best way.

For your Mod#2. You can just run the jumper with fusible wire from the alternator to the starter relay as you have done and leave the rest intact. Everything will work just fine and you won't be running any other wire. You are essentially bypassing the bulkhead for charging the battery.

Yes as John said that will work just fine. Your ammeter will no longer work though. Some guys connect a voltmeter in its place so it reads something. I removed "P" and "J" drilled them out and ran 8G wire to the ammeter leaving some extra under the dash. I also repaired the ammeter internally so it handles the current better (RTE) provides this service also. I also replaced every stinking bulkhead terminal male and female crimping and soldering. NAPA 725145 and 725147. A screwdriver should work to release the connector under the dash. I just left them in place while I changed the terminals. So if you could care less about the ammeter, you should be good to go.
 

MsBeep

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Today the modified and refurbished engine wire harness was put to the test, and SUCCESS is mine! The connections are tight and all my lights bright. Now that I have replacement wiring in hand, I know just what to do with it. Thanks again all for your most useful replies.
 

MsBeep

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was wondering where you've been...
Well, I've been to Oklahoma to pick up some parts that my very good friend had ordered for me. Drove my fuel sippin Import car down through the Dakotas, Iowa, Missouri, and the southeast corner of Kansas on my way. Spent a couple of hours in Arkansas, a few more days in Oklahoma, packed up my goodies and drove home. Now that I have it running, the rest is just icing on the cake. Until the next parts run...:beep:
 
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