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JD, if you look closely (ignore the writing) you will see the RED pertronix module wire going before the use of the ballast resistor, in a FORD, that would be under the dash technically... That's likely why it seems confusing to you. All Fords of the 60's & 70's need a separate power for the pertronix Red wire. in order for the pertronix to properly function as an on off switch. With a full 12V it's more sensitive to the magnetic pulse and gives a stronger on off signal to the coil.


Run the red to 12V Key ON and Key in Crank (ensure this wire does NOT get 12V in the ACC position.

Run the red with blue stripe to the coil + like it was before...
+1 :tup: (assuming the wiring is stock).

David
 

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I have to disagree with some of the comments. I have run a Pert I in my mustang for 15 years and it has always had the pink wire in circuit. It has always run perfectly. Always started though I can't say I have experienced a low batt condition that might have made it more difficult.

Pertronix always recommended bypassing the pink wire 'for best performance' they say. I don't say they are wrong and of course they are in the business of making money so they will say whatever they feel is best for them.

In my case I ran a rally-pac which requires the pink wire to be in circuit so the tach would work correctly and also to not damage it. So I didn't have any choice as long as I was using the rally-pac.

I also initially installed a Pert I in another ford and also left the pink wire in circuit since the rally-pac has been relocated to it from the mustang. So once again it needs the pink wire in circuit.

Then decided to replace the Pert I with a Pert III. My MSD timing controller wouldn't work with Pert I but does work with the Pert III. I'm still running the pink wire with the rally-pac and it still works just fine. The multi-strike and rev limiter still work as far as I know. I have observed the multi-strike part though I can't say I have pushed it to the rev limiter. Though that's not an important criteria for me.

The way I set mine up and have used it has worked for me whether it's right or wrong, never had any problems and never had a failure. Had it shown any problems I would have done what is needed to correct the problem. And I never had to do that. Either I did it right or was just lucky. Still lucky I guess!!
R

Com, what I've been saying for the last several posts is to USE the Original Pink wire with all pertronix but the multi-spark coil they make which is the Pert III coil I believe, but since I don't have any experience in multi-spark ignitions I left that part out. the 12 Volt to the unit it's self is a recommendation for the strength of the on off switch, but I am positive that even as little as 7 Volts will make that switch work flawlessly, it's simply a switch set off by a magnetic pulse, magnetic pulses have nothing to do with the voltage so it logically still works with lower voltage in my way of thinking. That's likely why you're having no issues with it.


As far as the MSD multi-spark coil goes, can you read your timing marks with a regular old school timing light without the marks floating back and forts 2 or 3 degrees? Or does it hop around a little bit.
 

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A few clarifications
not to get us off-topic...but-

PSIG- can we run a *stock* coil without the ballast resistor, as long as we're using a Pertronix II or III (ie- something with decent dwell control).

sorry for not being able to quote your statement that im referring to- it was the response to Comechero. apparently i'm doing something wrong and can't get the double-quote to show up.
 

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not to get us off-topic...but-

PSIG- can we run a *stock* coil without the ballast resistor, as long as we're using a Pertronix II or III (ie- something with decent dwell control).
Yes. This is not off-topic at all, as it is part of the confusion around it.

A "stock" coil will function fine with the P-II and no coil resistance, as it has dwell control to regulate the power to the coil. The performance will still be good (a bit better than stock), though diminished compared to using the coil PerTronix specifies or an equivalent.

A "stock" coil will fire with a P-III and no resistance for the same reason, however spark energy will be much diminished from optimal. This is due to the stock coil having greater primary resistance, induction, and a lower turns-ratio from the recommended HEI-style coil.

Also, because of the increased internal resistance and induction, the stock coil will not charge to saturation as fast as the HEI-style coil. This prevents the P-III multi-spark feature from having time to fire multiple starks (or as many) as it was designed to do. If it can still fire multi-spark, the sparks will be further apart or weaker, diminishing their value, and will cease at a much lower RPM as well. So, a stock coil will be both lower energy and fewer or no multi-sparks that are less effective. The rev-limit feature should continue to work normally.

The P-III is one of the first consumer versions of the "new wave" of multi-spark IDI (Inductive Discharge Ignition) systems allowed by modern technology, and will become the standard type used in years to come. While the classic MSD CDI (Capacitive Discharge Ignition) systems worked well to extend RPM and fire dirty mixtures in single-coil distributor systems, multi-spark IDI is better or higher-performance in nearly every way. Many race teams and classes of racing have already converted to MSIDI, and most all will within a few years. For example, with the move to EFI in NASCAR, offshore racing, and other endurance events, MSIDI will become a requirement to remain competitive, if for no other reason than to extend duration without refueling, or reduce the weight of on-board fuel for better performance.

David

Note to EEs and other electro-geeks: I am using terms like resistance, inductance, energy, etc. loosely to not distract from the essence of the subject.
 

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So...the requirement to use a ballast resistor (the pink wire) depends on two things:

1. the ability of the triggeing device to handle 12v
2. decent dwell control

Points can't handle 12v, and have bad dwell control
P-1 can handle 12v...but has bad dwell control
P-2 and P-3 can handle 12v, and have good dwell control- no resistor needed.

i think i got it. :)
 

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FE,
I have actually measured the voltage to the coil and have seen it as low as 6 v with the stock points and condenser. And of course the engine runs just fine. Of course this is a Kettering ign design so with the condenser in circuit it rings as it is supposed to. Don't know if the Pertronix does a ringing function though I suspect it must do something, maybe not as strong or ringing as long. Though with a multi-strike ign there can't be much time for ringing especially at high rpm's. I know Pertronix say their model III has not limit on the multi-strike and rings all the through the rpm range whereas most ign modules stop the function at around 3k. Not much time to get in many more firings above 3k anyway.

I have run an MSD ign with multi-strike and used a Pert I with pink wire in circuit as a trigger. The multi-strike worked fine there. I even tried an Accell 300 ign also with the Pert I as a trigger and with the pink wire in circuit. Once again it ran just fine as far as I can tell. Discontinued the Accell unit as my MSD timing controller would not function with the Accell.

So I switched to the Pert III and discontinued use of the Accell as the Pert III did all the same functions so was not needed. And the MSD timing controller works just fine with the Pert III alone.

I know they recommend bypassing the pink wire but I have not and have had no problems. Though I haven't had much opportunity to test it much in it's present setup. When I do I'll know even better how well it performs. And at that time due to the way I wired my setup I could easily switch the Ignitor to get a full 12v bypassing the pink wire.

I don't know what else to say other than the way I have used the Pert modules seems to have work for me.
R
 

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Just for reference here are my confusing instructions. To me looking at #13 and Figure 2 I should hook it up the way I currently have it and that's where it's confusing to me if you can't use the resistor wire to power the module.




 

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Comechero, other than losing partial or all function during low battery voltage situations (cranking, bad alternator, etc.), running the module with a resistor will work fine if it's only triggering secondary devices, such as an MSD box. This is because it is then only switching a very low-power trigger signal, and the module is handling almost zero electrical current. No power flow means no heat buildup due to low-voltage switching resistance. Much like using points to trigger an MSD box, the module will last virtually forever under those conditions where it has to handle almost no power.

However, if it is being used to control the coil directly (normal installation), then poor coil power switching (caused by resisted low-voltage) can cause abnormal internal heating with eventual problems or failure. One shade-tree method to determine if this is possibly the case, is to run the car to full temperature. Shut it down, pop the cap, and feel the module with your finger. If it's too hot to comfortably hold your finger on it for at least 3 seconds - you will have problems sooner than later. Also, feel other parts close to it, and if it's noticeably hotter than those, there's trouble brewing, and you need to bypass the resistor for full module voltage as PerTronix recommends.

To clarify switching resistance - if an electronic device (power transistor) is switched with low voltage, it may not turn fully "on". The power transistor is then acting as a form of resistor, and resistors make heat. Heat also promotes more resistance. Additionally, the power they are not transferring cleanly and fully reduces the performance of the load (ignition coil). HTH

David
 

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JD-

Look at #14 in the first photo.
In a ford, the "ignition switch side" of the resistor is that little 2" of wire coming out the back of your ignition switch, before it connects to the pink wire (the primary ballast resistor).
 

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JD-

Look at #14 in the first photo.
In a ford, the "ignition switch side" of the resistor is that little 2" of wire coming out the back of your ignition switch, before it connects to the pink wire (the primary ballast resistor).
I agree but for someone who only has these instructions and has no external ceramic ballast resistor like me would hook it up like I did in figure 2 and that is the wrong way. It sucks because without this thread or this site it would stay the way it is currently is hooked up.

Now does anyone know what wire would be a 12V run only wire on the factory 68 Galaxie harness or do I need to just run one that is on a switch?
 

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I agree but for someone who only has these instructions and has no external ceramic ballast resistor like me would hook it up like I did in figure 2 and that is the wrong way. It sucks because without this thread or this site it would stay the way it is currently is hooked up.
true. Ford did a few things kinda weird, and this is one of them.

Now does anyone know what wire would be a 12V run only wire on the factory 68 Galaxie harness or do I need to just run one that is on a switch?
Yes- just splice into the little 2" of wire between the ignition switch and the pink wire, and run that to the module.
 

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Yes- just splice into the little 2" of wire between the ignition switch and the pink wire, and run that to the module.
I was hoping for something under the hood instead of having to find a hole to run a wire through but it's a good thing the ignition switch isn't in the column on the early cars! ;)
 

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i agree but for someone who only has these instructions and has no external ceramic ballast resistor like me would hook it up like i did in figure 2 and that is the wrong way.
Exactly!
now does anyone know what wire would be a 12v run only wire on the factory 68 galaxie harness or do i need to just run one that is on a switch?
You need the wire to get power in both START and RUN. Take it from the switch like cuthrell said and the instructions show.
:tup:
David
 

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Will do David! As soon as we get a little better weather I will be hunting pink! :eek: Hehe!! Wait don't have to do that anymore as I got one. Lmao! ;) Yep I have a dirty mind!!



Cuthrell off topic but why are you a guest? Why aren't you signed up? You have good knowledge and belong here!! :D
 

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Sorry David but I'm a bit Electronically retarded, so forgive this little bit of my mind floating. You said teh dwell control of the II and III models made the coil safe for 12V.


Points Dwell on a good set of points is 24-29* or so right? It's pretty damn consistent without points bouncing so I'll say that under 6K (all my points cars took 6K no problem, not so huge on power at 6K with points but fine all the same) the Dwell is consistent. Isn't that a controlled Dwell? Does my thought make sense??

OK.

You say a Pert II and III have a better dwell control but the Dwell control is only the time frame that the coil is powering UP for a discharge, isn't that right?

So Technically BOTH Pert II and III switches having good dwell control is like a good set of points, and without a resistor the coil is going to fry just as if you were using points and have 12V direct to coil and not resisted...


Tell me where my logic has failed. Because in my eyes the coil has to be made for non reduced voltage in order to not need a resistor inline with the power to coil+. And Pert 1 and 2 Flame throwers and all other coil's not related to the use of the MSD ignition need Resisted voltage.


Please correct me so I can get this straight in my head, or congratulate me on an Einstein like moment in my miniscule life of ordinary-ness :) :) :)
 

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FE-

its not that the dwell isn't controlled well by the points- its that the points can't *vary* the dwell to match engine RPM.

points dwell (24-29, like you said) results in over-charging at idle rpm...and under-charging at 6000rpm.

modules like P-II, P-III, MSD, TFI, HEI, etc...can *change* the dwell as rpm increases/decreases. so- your coil doesn't get too hot and cook at lower rpms. and, you get more dwell time when you need it at higher rpms.
 

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No I am not getting it. How does the Pert unit control the dwell at the idle and say up to 2500 rpms.
All of the unit's I've seen are fairly simple switches If the dwell is teh timeframe they allow the coil to "fill up" then how does it vary enough over points to NOT burn up a coil?


I see dwell as measured in Degrees, not length of time, so at higher rpms I can understand how a programmable Unit can increase the dwell time and allow deeper coil fill, but I don't see how these simple pertronix switches can adjust the Dwell to be Shorter at low rpms and Longer at high rpms without a control box, which I dont 'see with a Pertronix unit....

Any help for me there?
 

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Bingo - cuthrell is on it. Let's pretend you are watering plants in your yard with a couple of buckets and a faucet. Think of the coil like a bucket, and the water flowing into it is from a faucet. So you fill one bucket, and put the other under the faucet so you can let it fill while you walk over to the other side of the yard to dump the first bucket.

If you have the faucet on full-blast, the bucket will overflow before you walk back to the faucet. So, you turn the faucet down to restrict the flow of water to give you time to make the trip without it overflowing. That's like adding a resistor to a coil circuit so it won't overflow (overheat). :tup:

Now, you have to hurry the job to get done, so you begin to run back and forth. But, the bucket you left filling is not full when you get back. You can't wait, so you take the bucket even though it's only part-full. That's what happens to a coil with resistance and fixed-dwell like points. The coil does not overflow and cook, but it doesn't fill-up at higher revs for a hot spark either. With a weaker spark, you lose power and efficiency. With higher performance engines (especially with higher compression) the coil power becomes so weak it will stop sparking entirely. This is often called spark dropout or blowout and feels like a random rolling miss, valve float, or a rev-limiter - and your power is falling-off before you can feel it. :(

But, what if you had a "smart" faucet, that would turn the water on full-blast, but would turn the water off when the bucket was full right when you got back? It would never overflow. Even better, as you ran faster and faster, the bucket would always be full every trip, because it would turn-on full-blast and be full by the time you got back. That's controlled dwell. No resistance, as it shuts-off flow before it's too much, but it controls how long the faucet is open so it can saturate the coil completely for a strong spark even at high revs to prevent power and efficiency from falling-off, or complete spark failure. :D

So, I hope that analogy helps to understand the concept. As for how it's done, there are two common methods to accomplish this - dwell timing and current limiting. Really smart modules like the Ford EDIS, newer EECs, and MSIDI systems can calculate exactly when to turn the power on through the coil, so it's full right when it has to fire. That's dwell timing, and true variable controlled dwell. It limits the time of coil power flow, therefore limiting the total current the coil sees for any one firing.

The other way with older less-advanced modules like the GM 4-pin is to use fixed dwell angles, and let the coil charge at full power, but when it's fully saturated the module will limit current flow to hold it at that level until the coil fires. It acts like it's own built-in resistor, but can reduce the resistance as RPM increases to always have a stronger spark. This is current-limiting, but as the effect is so similar to dwell control, it is usually lumped into the same category. Some systems use both methods together, so it can get really messy talking about it all.

David
 
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