Ignition wire and turn signal identification help

[Ripper679]

Hello all!
Ok, so I've decided to attempt to install a low oil pressure engine kill switch on my 73 Coupe. The instructions say," Install the switch somewhere in the oil pressure system and route the power for the ignition system (NOT start function) through this switch. When the oil pressure drops below 12 psi it will shut off the ignition".

My entire car is in pieces. Can someone please let me know what ignition wire I should tap into that isn't part of the cranking function? Or is there a better switch available than the one I listed below? Running this because I plan on a remote dual oil filter and an external oil cooler for track days.

Thinking about using this switch:
https://www.longacreracing.com/tech...-fuel-pump-shutoff-switch-wiring-instructions
Also.... one last question.... installing a dakota digital dash..... can someone please let me know what color the right vs left turn signal wires are so I don't hook them up backwards? Mine were not connected when I got my car.


Kick ass and
Thanks!!!
Manny

 

[Doug's 73 Mach1]

run stop, red/ light green stripe at the coil. Left is light green/ white stripe, Right is white/ light blue stripe

 

[boilermaster]

Ripper679,
By stating you are using the Dakota digital dash, that means non factory tachometer, but what ignition system are you running and what voltage does it require.
Do you intend to have the switch enabled or disabled during cranking ?
Wiring diagrams from both the Dakota digital dash and your ignition system will go a long way here to get some competent answers to your questions.
I had a Dakota Digital dash in my Shovelhead Harley FXR, really liked the performance menu,
0 - 60 mph times, 1/4 mi. time/speed, top speed, max rpm and electronic gear read out.
Still remember a 3.9 sec. 0 -60 mph time on a stock sized tire.

 

[Ripper679]

Yeah, I'm running an MSD 6al ignition. The dash is plug and play but all the wires are disconnected and I only had a question on what wire was for the right and left turn signal indicator. For the ignition wire, I just need to know what wire is the non cranking ignition wire for the switch.

That wire will go in and out of the oil pressure switch and when oil pressure drops it will open the connection to said wire, killing the ignition.




Probably.



Either way..... just hoping I can get that particular wire identified with this forums help.

Thanks!
Manny

 

[Hemikiller]

The MSD powers the coil itself, not through the factory ignition. You'll want to kill the MSD by routing the light gauge red MSD wire through the oil pressure switch. You can use the Red w/yellow hash mark in the engine gauge harness, as it is hot in run and start.

 

[Ripper679]

Sweet, thats a great idea! So I'll just route the light gauge red MSD wire to one side the switch and coming out of the other side of the switch the light gauge red wire will go to the red w/yellow wire. Essentially using the switch to break continuity between the red w/yellow wire and the light gauge red MSD wire killing the ignition?

 

[Hemikiller]

Yep, that's what I was thinking.

 

[Ripper679]

Thanks so much for suggestion!!

That said....
Just out if curiosity... is this red/yellow wire the previously mentioned ignition wire (the one without start function) that I was supposed to be looking for in my first post?

 

[mrgmhale]

You have several solid posts already, so I will not add confusion by simple repeating what you have been told. Yet, I did want to weigh in, so to say, just to let you know the guidance you have received from both Doug and HemiKiller already is right on. We have a Dakota VHX dash on both of our 1973 Mustangs, and the 73 Mach 1 also has the MSD 6AL ignition system. But I do not have an engine oil pressure kill switch. But, I still agree with HemiKiller re: his comments on the matter. He has always been dead on in his assessments I have read.

In case you are not familiar with the Red Wire with Yellow Hash Marks, which feeds the Throttle Position Solenoid (Circuit #640), I have a YouTube video that shows where it is located. If your Circuit #640 is not there (someone cut that wire from the main harness on our 73 Mach 1!) there is al alternative switch power source with the Wiper Motor you can also tap into. I cover that in another YouTube video. Those links are: