1973 cuda wiring harness help

[Dchase3]

When replacing factory points ignition with and electronic ignition (ready to run distributor ). Where should the yellow, black, brown, & dark blue wires go on the under dash harness since I’ll be bypassing the ignition ballast?

 

[72RoadRunnerGTX]

Ready-to-run ignition sense? No need to mess with wiring under the dash. At the ballast resistor being removed, connect the dark blue wire (ignition 1) to the brown wire (ignition 2) together for 12-volts in both crank and run.

 

[Dchase3]

Ready-to-run ignition sense? No need to mess with wiring under the dash. At the ballast resistor being removed, connect the dark blue wire (ignition 1) to the brown wire (ignition 2) together for 12-volts in both crank and run.

Let me elaborate more. I bought this 73 cuda earlier this year. It has a 360 magnum crate motor. Not original motor. It has a blueprint engines pro billet ready to run distributor and coil. Currently there is no ignition ballast resistor. I want to replace the factory under dash harness because it’s clearly been messed with has a lot of splices.
Currently the blue wire goes to bulkhead disconnect and then to the e-choke for carb. Brown wire goes to bulkhead disconnect and stops. Goes nowhere inside engine bay. There is a yellow wire running to #20 space in bulkhead that goes to starter relay.
The wire going to the positive side of coil comes from a seperate toggle switch that has to be flipped for car to start - previous owner installed.
I would like to eliminate that toggle switch when I re-wire. Trying to confirm what I should do with the blue and brown wires.

 

[72RoadRunnerGTX]

Leave the yellow starter relay wire out of the picture for ignition, should be in cavity 9 however. You want ignition 1 (dark blue @ cavity 23, power when in run position only) and ignition 2 (brown wire @ cavity 22, power in crank only) connect them together with the ignition sense from the ready-to-run distributor. If the brown wire is missing on the engine compartment side, you could add one at #22 or bridge them on the dash side. The dark blue wire on the dash side typically has a white trace as well.

 

[pschlosser]

If a bunch of stuff has been altered, the colors of the wires you indicate may not have much meaning. You may need to confirm what is connected to where.

I recommend you seek out a wiring diagram. There are several places online to download the 1973 Factory Service Manual(s), and/or the majority of the 1970-74 manuals. Any of them may work for this project. All for free, just by searching google.

The wiring diagrams in these manuals are really nice to have.

There are a number of brown wires in the harness, so it's difficult to discern to which on you refer.

The ballast resistor was originally designed to reduce the coil voltage once the engine was started, to add longevity to the points. It's unlikely you need this, with your newer system. So as others have said, among the things you may want to confirm and change, is bypassing the ballast resistor by connecting the (presuming the wire colors correct) dark blue (DBL) and brown (BR) wires (of the engine wiring harness going to the ballast resistor) together and that will feed the positive side of the coil.

Typically, the DBL wire feeds a bunch of things, and connects to one field of the alternator.

 

[Dchase3]

Leave the yellow starter relay wire out of the picture for ignition, should be in cavity 9 however. You want ignition 1 (dark blue @ cavity 23, power when in run position only) and ignition 2 (brown wire @ cavity 22, power in crank only) connect them together with the ignition sense from the ready-to-run distributor. If the brown wire is missing on the engine compartment side, you could add one at #22 or bridge them on the dash side. The dark blue wire on the dash side typically has a white trace as well.

Ok this makes sense. I can easily add a brown wire at the #22 spot engine side. If I do this. How would I hook up the electric choke ? Since it’s currently using the DBL wire at #22

 

[Dchase3]

If a bunch of stuff has been altered, the colors of the wires you indicate may not have much meaning. You may need to confirm what is connected to where.

I recommend you seek out a wiring diagram. There are several places online to download the 1973 Factory Service Manual(s), and/or the majority of the 1970-74 manuals. Any of them may work for this project. All for free, just by searching google.

The wiring diagrams in these manuals are really nice to have.

There are a number of brown wires in the harness, so it's difficult to discern to which on you refer.

The ballast resistor was originally designed to reduce the coil voltage once the engine was started, to add longevity to the points. It's unlikely you need this, with your newer system. So as others have said, among the things you may want to confirm and change, is bypassing the ballast resistor by connecting the (presuming the wire colors correct) dark blue (DBL) and brown (BR) wires (of the engine wiring harness going to the ballast resistor) together and that will feed the positive side of the coil.

Typically, the DBL wire feeds a bunch of things, and connects to one field of the alternator.

Thanks. I do have a field service manual with wiring diagrams. I’ve been studying it. I can trace the DBL wire and the BR wire to the ignition switch harness they don’t seem
to be messed with. The DBL also has a splice that runs to the fuse box. The yellow wire seems like it runs to the starter relay and the starter itself. And then the toggle switch the previous owner installed is getting its power from a big junction of wires - blk ammeter wire, red wire from dash harness, blk headlight power wire, and another blk wire that looks like it goes to bulkhead

 

[72RoadRunnerGTX]

Ok this makes sense. I can easily add a brown wire at the #22 spot engine side. If I do this. How would I hook up the electric choke ? Since it’s currently using the DBL wire at #22

Ignition 1, DBL should be in cavity 23 originally, electric choke , one alternator field connection and voltage regulator (assuming you are still running a stock alternator) will also be on that circuit, leave them there, just connect ignition 2 (brown wire) to that circuit to have voltage while cranking for the aftermarket ignition sense. I would lose the added switch.

 

[Dchase3]

Ignition 1, DBL should be in cavity 23 originally, electric choke , one alternator field connection and voltage regulator (assuming you are still running a stock alternator) will also be on that circuit, leave them there, just connect ignition 2 (brown wire) to that circuit to have voltage while cranking for the aftermarket ignition sense. I would lose the added switch.

Sorry DBL is in cavity #23. BR in cavity 22. On the engine side a wire comes out of the cavity and runs straight to electric choke. Not using stock alternator so the voltage reg has been eliminated.

 

[Challenger RTA]

Engine compartment.