Pertronix 1381a

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Here's another version of the piggy back terminal.
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Either one allows the original wire and connector to remain intact.


A little confusion can come from the diagram saying wire to ignition. Most people think of power as coming from positive. So rewrite that in your head as wire from ignition. What that really means is ignition switch's 'run' wire. Its generally dark blue or dark blue with stripe.

Ballast resistor or not. The ballast resistor is there to control the amount of current flowing through the coil. IF this particular Pertronix system has a current controller for the coil built in, then the ballast is not needed. If it doesn't have a controller in it, then the ballast is needed.
 
Mattax said:
Here's another version of the piggy back terminal.
View attachment 1715583273

Either one allows the original wire and connector to remain intact.


A little confusion can come from the diagram saying wire to ignition. Most people think of power as coming from positive. So rewrite that in your head as wire from ignition. What that really means is ignition switch's 'run' wire. Its generally dark blue or dark blue with stripe.

Ballast resistor or not. The ballast resistor is there to control the amount of current flowing through the coil. IF this particular Pertronix system has a current controller for the coil built in, then the ballast is not needed. If it doesn't have a controller in it, then the ballast is needed.
Click to expand...
Thanks that makes sense I posted a pic of my ballast resister a couple posts back, blue and blue striped on one side brown on other and I’m pretty sure the brown goes to the coil so it only makes sense to go with the blue wires other wise I could just put the red terminal from pertronix right on the coil thanks a lot for making that clearer!
 
The other brown wire comes from the key switch ignition 'start' position. This way when the battery voltage is being drawn down during starting the resistor is bypassed.
 
Called pertronix today just to make sure I am sure what I’m doing, he said not to use copper core plugs what are you guys using who run the pertronix kit?
 
He didn’t say maybe I’ll call back tomorrow and ask ,he said the worse things for the electronic kit is unsurpressed wires and copper core spark plugs, you would think if that was true they would tell you in the instructions
 
Chub380 said:
I emailed them,Johnny dart is a new distributor a better option?
Click to expand...

Depends who you ask. I'm not a fan of Pertronix. I consider it a bubble gum ignition. I like the Chrysler electronic ignition.
Millions of miles of dependable service. Just my opinion.
 
I’m starting to wonder that too, when I recieved the email today about the spark plugs they told me everything but something about plugs
 
Called them back said it has nothing to do with the plugs just wires they were not sure why someone said that, but to make things more confusing the guy told me today black wire on negative side of coil red on positive side of coil(from the kit/distributor) then run a switched 12v power wire to the positive side of the coil as well ,this seems to me I’m bypassing the resister which the instructions say not to do I told him my coil is 1.5 ohm and he said that’s right it matches the 1381a. How could something so small be so confusing ,fig3 above looks like nothing like he said.
 
He’s telling me to do it like fig2 totally two different things
C2C58479-7D12-474F-BB9B-BBF9FF153C98.jpeg
 
Ok, good. Yeah spiral core wires. That's what most are nowadays.

I would wire it like figure 3. Full 12v to the Pertronix and the other end of the resistor to the coil.
 
Yeah it was good to hear about the plugs, I think they need to take some time and have all the techs get on the same page nothing worse than each person telling you something different
 
Sounds like whomever answers the phone/email actually has no clue as to how the thing works.

What do we know.
To run the device, a "12 Volt" source of power is needed.
That's actually somewhat vague. More helpful will be if the instructions say it will draw x amps at 12 Volts. Also would be good to find out the minimum supply voltage needed.
However this diagram implies the unit will operate at less than 12 Volts during startup.
upload_2020-8-25_22-6-40.png


As to whether it has a current controller.
Best I can tell the basic "Ignitor I" is nothing more than a points replacement open/closed for the coil. Therefore everything else remains stock.
The Ignitor II kits claim to have adaptive dwell (so in theory would be as good as dual points at high rpm), and these claims
  • Synchronized peak current and spark timing reduces heat build-up
  • Senses start-up and develops more energy for quicker, easier starting
which suggest there may be a current controller for the coil (at least on some).
 
Figure 3 tells me the ignitor(part in distributor) would have 12v a soon as the key is turned but the power to the coil would still be taking its traditional path through the resister
 
I had one guy tell me fig2 and one fig 3 also a lot of talk about burning the ecu if fig 2 is used
 
upload_2020-8-25_22-25-40.png


3. is for your car as it has a ballast resistor.

2. The 1.5 ohms is referring to the resistance in the primary circuit of the coil. The primary circuit is the circuit that sends low voltage power through the coil. This induces a charge in the secondary windings of the coil.
 
Exactly that’s why I’m frustrated I read all that I think that’s talking about if you don’t change the coil. But I got the one they said and it had 1.5 resistance also
 
And I told the guy on the phone today all the parts I had 1381a and 40111coil and he said fig2 makes no sense
 
Chub380 said:
Figure 3 tells me the ignitor(part in distributor) would have 12v a soon as the key is turned but the power to the coil would still be taking its traditional path through the resister
Click to expand...
The confusion here is someone at peteronix dumbed down/simplified things so they no longer match reality. :BangHead:

When we hit the start -
Battery power gets drawn down to something less than 12 Volts. It could be as low as 9 or 9.5 Volts and still be good enough to get started.
So that's why it would be good to know if the minimum voltage the Ignitor unit will need to operate.
upload_2020-8-25_22-42-26.png


But it seems pretty clear to me that the instructions are saying this will work, and survive. So not much gained by trying to find out what minimum voltage is needed. If it works it works.

If you want to check the resistance in the coil's primary windings, measure the resistance from coil plus to coil negative.
This is the specs from a '70 Plymouth FSM, for a 318. My recollection is all of the coils and ballast resistors of this era have specs close to these.
upload_2020-8-25_22-47-10.png
 
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Chub380 said:
Exactly that’s why I’m frustrated I read all that I think that’s talking about if you don’t change the coil. But I got the one they said and it had 1.5 resistance also
Click to expand...
Sometimes I've got wonder if they just want to sell parts...
 
I think that’s exactly it. I’ll check it tomorrow but it’s a brand new one from them and it says 1.5 right on it.
 
Since you already have it, it won't hurt to install a new coil even if it is the same resistance. Your coil could be original.

@Mattax you have a great way of explaining electric circuits!! I worked on electronic radios in the Air Force and have to think an auto circuit through!!
 
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