Bulkhead wire 64 Barracuda

[robcuda]

Hello Gentleman,

(64 Cuda, 273)
In preparation for installing a HEI system I am trying to resolve this bulkhead wire problem. Currently the fused wire shown (with 30 amp fuse) has blown a couple of times while driving. The connection at the bulkhead is flimsy (the male tab on wall is not completely secure).

-Would you recommend I drill through the wall and replace with a fusible link?
-Are there any other power wires I should pass through firewall?
-If this works and I can move on, what power source do you recommend for the HEI?
-should I bypass the ballast?
-Also, would it make sense to do a Ammeter Bypass before HEI install?

Thank you in advance, any help would be appreciated!
Rob

Here is a link to the HEI system on order
MOPAR Small Block 273-318-340-360 Red SMALL CAP HEI Distributor & 50,000 V Coil

 

[KitCarlson]

Here are a few observations.
I am not familiar with the 64 wiring it differs from my 66, without the bolted connection in bulkhead connector. The 66 has a #10 feed cable from + battery terminal. It looks like the feed from the large post of the starter relay needs attention, the 30A fuse looks like a repair to perhaps replace a fusible link. I added up load estimates, wipers 5A, alt field 3A, ignition 4A, heater fan 8A, headlights 10A, and radio 4A, for total of 36A. So that current could blow the fuse, while running all loads at once.

The HEI ignition has a peak current of 4.6A with average current much less than that, because the current ramps up, just before needed, so it draws less average current than a points and ballast system.

Instead of drilling a firewall hole, some drill the bulkhead connector, and join with a barrel crimp for a solid connection.

Relays are often used to feed under hood loads from direct battery feed, switched by energizing relay with original circuit. One 30A Bosch type relay can be used to power the ignition and IGN terminal of regulator, the relay coil is powered from the point where IGN1 and IGN2 are joined to eliminate ballast resistor. The other coil terminal is connected to ground.

A voltmeter is often used to measure wiring/connection voltage drops in circuits. Drops more than 0.1V typically need attention. So measuring may save time, by not fixing what is working, and verifying improvements.

 

[65 Dartman]

I can't say about the 64. The 65 has 2 solid buss bars, one of which connects to the output terminal on the alternator and the other to the big lug on the starter relay. On the inside the wire that connects to the battery (via the starter relay) goes directly to the amp gauge. The other wire on the amp gauge routes back to the wire from the alternator. This wire has a splice with wires going to the ignition switch and headlight switch. Again, this is on the 65; the 64 might be different.

 

[robcuda]

Here are a few observations.
I am not familiar with the 64 wiring it differs from my 66, without the bolted connection in bulkhead connector. The 66 has a #10 feed cable from + battery terminal. It looks like the feed from the large post of the starter relay needs attention, the 30A fuse looks like a repair to perhaps replace a fusible link. I added up load estimates, wipers 5A, alt field 3A, ignition 4A, heater fan 8A, headlights 10A, and radio 4A, for total of 36A. So that current could blow the fuse, while running all loads at once.

The HEI ignition has a peak current of 4.6A with average current much less than that, because the current ramps up, just before needed, so it draws less average current than a points and ballast system.

Instead of drilling a firewall hole, some drill the bulkhead connector, and join with a barrel crimp for a solid connection.

Relays are often used to feed under hood loads from direct battery feed, switched by energizing relay with original circuit. One 30A Bosch type relay can be used to power the ignition and IGN terminal of regulator, the relay coil is powered from the point where IGN1 and IGN2 are joined to eliminate ballast resistor. The other coil terminal is connected to ground.

A voltmeter is often used to measure wiring/connection voltage drops in circuits. Drops more than 0.1V typically need attention. So measuring may save time, by not fixing what is working, and verifying improvements.

Thank you KitCarlson for the quick reply! Very helpful!
-Yes, I think you're right it must have been a fusible link at one time.
-Also, not be an wiz electric guy myself, your addition of approx amps from various accessories helps me judge things much better.
-Great to also know how much the HEI will draw, I'm surprised at how little!
-will attempt to drill through old connection

Thank you again!
Rob

 

[robcuda]

I can't say about the 64. The 65 has 2 solid buss bars, one of which connects to the output terminal on the alternator and the other to the big lug on the starter relay. On the inside the wire that connects to the battery (via the starter relay) goes directly to the amp gauge. The other wire on the amp gauge routes back to the wire from the alternator. This wire has a splice with wires going to the ignition switch and headlight switch. Again, this is on the 65; the 64 might be different.

Thank you Dartman! Your input is appreciated. Even though your set up may be a little different, your notes will help me figure it out.
-Do you recommend an ammeter bypass? Did you bypass on your 65?
-Found shop manual for 65 but still looking for a 64 because of some of the differences.

Thank you!
Rob

 

[66fyssh]

I'm not familiar with the 64 either. I would replace the fuse wire with one continuous lead from each side of the fuse. You should also be able to disconnect the bulkhead connectors and clean up the terminals. Many folks replace the terminals with new Packard 56 terminals. I just cleaned both sides of mine with a small file and packed it with dielectric grease. I kept my amp gauge but did the fleet bypass. Again, not sure how the 64 is wired.

 

[65 Dartman]

Thank you Dartman! Your input is appreciated. Even though your set up may be a little different, your notes will help me figure it out.
-Do you recommend an ammeter bypass? Did you bypass on your 65?
-Found shop manual for 65 but still looking for a 64 because of some of the differences.

Thank you!
Rob

An ammeter bypass certainly makes sense. I am using a Dakota Digital conversion to my instrument cluster (a 66 Barracuda cluster) which uses a voltmeter. I am also not using the 65 Dart underdash harness but a modified 80-83 Mirada harness in which I am using an added solid lug in the bulkhead connector - 2 go directly to the Mirada ignition switch (using a Mirada steering column) and the other directly to the headlight switch. My underhood harness is also modified with headlight relays and fuses to protect the relays, alternator wiring and the 3 hot wires going to the aforementioned 3 solid lugs. I upgraded my alternator output wiring in size and routed it directly to my junction box which is also tied to a lead from the Positive battery cable. Hope it makes sense.

 

[robcuda]

An ammeter bypass certainly makes sense. I am using a Dakota Digital conversion to my instrument cluster (a 66 Barracuda cluster) which uses a voltmeter. I am also not using the 65 Dart underdash harness but a modified 80-83 Mirada harness in which I am using an added solid lug in the bulkhead connector - 2 go directly to the Mirada ignition switch (using a Mirada steering column) and the other directly to the headlight switch. My underhood harness is also modified with headlight relays and fuses to protect the relays, alternator wiring and the 3 hot wires going to the aforementioned 3 solid lugs. I upgraded my alternator output wiring in size and routed it directly to my junction box which is also tied to a lead from the Positive battery cable. Hope it makes sense.

Thank you for the response! Some went above my head, but main thing is you agree with the ammeter bypass. I'll let the rest soak in and see what I can gain from it.

Cheers!

 

[robcuda]

An ammeter bypass certainly makes sense. I am using a Dakota Digital conversion to my instrument cluster (a 66 Barracuda cluster) which uses a voltmeter. I am also not using the 65 Dart underdash harness but a modified 80-83 Mirada harness in which I am using an added solid lug in the bulkhead connector - 2 go directly to the Mirada ignition switch (using a Mirada steering column) and the other directly to the headlight switch. My underhood harness is also modified with headlight relays and fuses to protect the relays, alternator wiring and the 3 hot wires going to the aforementioned 3 solid lugs. I upgraded my alternator output wiring in size and routed it directly to my junction box which is also tied to a lead from the Positive battery cable. Hope it makes sense.

Hey Dartman,
Thanks for mentioning the headlight relay upgrade. I think I will do this straight away. Thus far, is seems as though the headlights are one of the biggest draws.

Best

 

[BillGrissom]

In my 64 Valiant, I installed a 65 Bulkhead from a Fury. Had to cut the hole 1/8" taller.

 

[robcuda]

In my 64 Valiant, I installed a 65 Bulkhead from a Fury. Had to cut the hole 1/8" taller.

Thank you for the info! Appreciate it!

 

[65 Dartman]

I am also not using the 65 Dart underdash harness but a modified 80-83 Mirada harness in which I am using an added solid lug in the bulkhead connector - 2 go directly to the Mirada ignition switch (using a Mirada steering column) and the other directly to the headlight .

In my 64 Valiant, I installed a 65 Bulkhead from a Fury. Had to cut the hole 1/8" taller.

I should mention that I am using a 65 Dart bulkhead connector in my modified Miranda harness

 

[BillGrissom]

I should mention that I am using a 65 Dart bulkhead connector ...

It appears the OP is also, per photos in post 1. Sorry, I couldn't see them when I made post 10 from a cell-phone. Wonder why - modified?, late 64 with 65 parts?, Cudas different than Darts & Valiants? No problem if the ALT and BAT feed-thrus wiggle slightly in the plastic bulkhead, since that is not an electrical connection. The only connection is at the bolt in the engine bay. The cabin side is crimped and/or soldered to the 12 awg wire. All you might need is to unbolt, sand the connections and re-bolt. I coat w/ silicone grease, but battery anti-corrosion spray should also work.

Not surprising that a 30 awg fuse keeps blowing, since that BAT wire carries the charging current from the alternator (up to 60 A, depending on alternator). Indeed, it carries all current flow in or out of the battery, less transient underhood loads (starter & horn). While upping the fuse, you might re-work that gomer'ed wiring. There shouldn't be any exposed copper and strange it has 2 butt crimps where none are needed, plus those things scream, "amateur".