pertronics

[corbins]

Hi, working on a 69 CJ car. Trying to determine which wire at the ignition switch is a 12 volt "switched" source to run the Pertronics off of. On my 68 , 2185, I think it was the "c" post of the switch. Any ideas on where to tap a 12 volt switched lead ?

Thanks !

[69 GT350 Vert]

I have a pertronix on my 69 shelby.  I used a multi meter and confirmed I had 12 volts on the coil wire from the engine gauge feed harness at both start and run positions of ignition switch.  So I just used that wire in the engine bay and didn't have do any wiring under the dash to install the pertronix.  It has been working for 10 years just fine.  My car is a tach car so if your car has a tach, it may work the same as mine. 

[corbins]

Thank you, I will defiantly check that. It would sure be easier than what I had to do on 2185.
Appreciate the response !!

Steve

[67350#1242]

It is best if you can tap the switched 12v before the pink resistor wire, if you have a tach you can "Y" off the ign. side of the tach connector.  This will give you clean 12v without the resistance in the circuit.  I have some diagrams but wont let me post:
"uploader full".  Kurt
(able to upload diagram by modifying orig message)

[67 GT350]

Good to know, can you email me your diagrams? Fran
franimal007@hotmail.com

[69 GT350 Vert]

On my '68 Shelby, the voltage at the same coil wire was much less than 12 volts, so I couldn't use it for pertronix.  On my 69, it was over 12 volts, so I used it.  Not sure how the "resistor" wire works, I thought it was supposed to reduce the voltage to the coil to below 12 volts, but that is not the case on my '69 shelby.  If you have 12 volts at start and run position of ignition switch, it should work fine. 

[Bob Gaines]

On my '68 Shelby, the voltage at the same coil wire was much less than 12 volts, so I couldn't use it for pertronix.  On my 69, it was over 12 volts, so I used it.  Not sure how the "resistor" wire works, I thought it was supposed to reduce the voltage to the coil to below 12 volts, but that is not the case on my '69 shelby.  If you have 12 volts at start and run position of ignition switch, it should work fine.

If you have 12 volts in the run position out to the coil then your resistor wire is wired inline with your harness is probably defective.12 volts to the a Ford yellow top coil will eventually cook the coil over time. It will get real hot. It is the same thing that happens when hot wiring a early Mustang /Shelby to by pass the key. Some coils have a internal resister which can use 12 volts and not burn up. Others are designed to use external resister like what is made into the Mustang harness so they do not burn up.

[67350#1242]

Not sure how the "resistor" wire works, I thought it was supposed to reduce the voltage to the coil to below 12 volts, but that is not the case on my '69 shelby.  If you have 12 volts at start and run position of ignition switch, it should work fine.

You will only see a voltage drop at the coil if the points are closed or if the Pertronix is conducting (during the dwell time).   If points are open or Pertronix off no current is flowing and you are simply reading battery voltage.  (No current = no voltage drop).
As far as I know all these cars that used the yellow top coil were meant to have resistance in the battery feed to protect the coil from burning up - that would include the 69's.
Someone correct me if I'm wrong.
Sorry Bob don't mean to repeat but your post came as I was replying.

[1967 eight barrel]

I am running a Pertronix II on my 67 500. I used a scotch lock and pulled off the wire to the tach, through the boot on the firewall and directly to the red on the module wire from the distributor.  Just to let you know, you will have 12V at the coil momentarily when you start the vehicle. When you let the key back into the run mode it has between 6-9V.   
                                                                                    -Keith

[2112]

I am running a Pertronix II on my 67 500. I used a scotch lock and pulled off the wire to the tach, through the boot on the firewall and directly to the red on the module wire from the distributor.  Just to let you know, you will have 12V at the coil momentarily when you start the vehicle. When you let the key back into the run mode it has between 6-9V.   
                                                                                    -Keith

Keith, are you running a stock style coil?

[1967 eight barrel]

 I am running the Pertronix II and matching coil with the Marty Concours reproduction ignition wires and NGK plugs. When I pulled the power pre-tach it stays at 12V constant and starts easier.  I see people post often about the units failing. It usually happens to those who do don't follow directions and don't run 12V constant. The low voltage kills them. Any of the Mustangs/Shelbys that are ran through the resistance wire only have 6-9 volts once the key is released to the run position.
                                                                                                      -Keith