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Some of you will remember the conversion kits Mopar sold under Direct Connection
(and later, Mopar Performance) that included everything needed to convert a points
type ignition to Chrysler electronic ignition.
The kits typically included a new distributor, ECU control unit, a ballast resistor and the required wiring harness.
This was easy to do because Chrysler intentionally used as much of the points type
distributor design as possible in going electronic, so much so that the rotor and caps
worked fine on either and were interchangeable.
The instructions that came with the kit were simple but in typical DC fashion were VERY complete and totally useful in not only installing the kit, but tuning afterwards.
I keep a copy of those instructions to this day.
They even offered (and still do) a "conversion" electronic voltage regulator that uses
the factory wiring to replace the old points type units too, as a constant voltage benefits electronic ignition properly operating.
I've most always converted whatever car I had to electronic using those kits because they just plain worked, were simple to reverse later if desired, and all my cars were street cars
with something resembling stock engines.
Never had a worry about doing so. Parts (if rarely needed) were simple and cheap.
The Accel heavy cap that closely resembles the factory distributor cap even works on either type factory distributor also, as does their rotors and I use both.
All that said, on to the point of my post:
The GTX I have now came with a manner of electronic ignition conversion already done.
They didn't use the ballast provided in such a kit, instead cobbling some sort of "double" ballast off of some later Mopar in the stock location (it appeared they ripped that harness, the ballast and some generic control unit out of a mid-70's model of some sort).
I corrected all that to the "proper" harness and installed a control unit I had in my stash,
the typical "orange box" Mopar unit included in the kits as well.
For an ignition coil, I currently have the popular "Blaster II" unit from MSD, connected by stock harness.
Well, Ed got to thinking too much a while back....
In an effort to get maximum spark to the plugs, I got to thinking that since the Blaster II doesn't require an external resistor when used with electronic ignition, I'd replace the stock ballast resistor (or even eliminate it).
I experimented with different rated ballast resistors, took a bunch of meter readings at the coil for voltage reaching it, all that "thinking too much" stuff.
Currently, I have a ballast that is rated to damn near nothing (like 0.4 ohms) on the car, trying to get the full 12VDC through the system.
In the end, I don't think it made that much difference either way.
BUT....
Have I negligently caused possible harm (or at the least, messed with) the function of any OTHER parts of the ignition system in doing so?
What about the Mopar ECU? Does it matter what voltage gets to it?
Anything inside the stock distributor affected by what I've done?
Reason I ask is I'm chasing down a slight "jittery" run condition under very light load, low RPM conditions (say, going down main street at 30mph at like 1700RPM) where the engine can be felt just ever so slightly doing a little jittery "dance".
(The same situation can be almost imperceptibly observed sitting still and revving the engine gently above 1500RPM or so, up over 2000RPM). There's tiny little half-assed jitters going on.
NOT actual misfires or anything like that and the condition can be quickly overcome with more throttle and/or load applied; further, when the car is accelerated, there's no issues and all functions like it should.
Am I chasing after minutiae here? Does the ballast have anything to do with this?
Does anyone know what the rating of the ballast resistor sold in the Mopar conversion kits was/is?
(and later, Mopar Performance) that included everything needed to convert a points
type ignition to Chrysler electronic ignition.
The kits typically included a new distributor, ECU control unit, a ballast resistor and the required wiring harness.
This was easy to do because Chrysler intentionally used as much of the points type
distributor design as possible in going electronic, so much so that the rotor and caps
worked fine on either and were interchangeable.
The instructions that came with the kit were simple but in typical DC fashion were VERY complete and totally useful in not only installing the kit, but tuning afterwards.
I keep a copy of those instructions to this day.
They even offered (and still do) a "conversion" electronic voltage regulator that uses
the factory wiring to replace the old points type units too, as a constant voltage benefits electronic ignition properly operating.
I've most always converted whatever car I had to electronic using those kits because they just plain worked, were simple to reverse later if desired, and all my cars were street cars
with something resembling stock engines.
Never had a worry about doing so. Parts (if rarely needed) were simple and cheap.
The Accel heavy cap that closely resembles the factory distributor cap even works on either type factory distributor also, as does their rotors and I use both.
All that said, on to the point of my post:
The GTX I have now came with a manner of electronic ignition conversion already done.
They didn't use the ballast provided in such a kit, instead cobbling some sort of "double" ballast off of some later Mopar in the stock location (it appeared they ripped that harness, the ballast and some generic control unit out of a mid-70's model of some sort).
I corrected all that to the "proper" harness and installed a control unit I had in my stash,
the typical "orange box" Mopar unit included in the kits as well.
For an ignition coil, I currently have the popular "Blaster II" unit from MSD, connected by stock harness.
Well, Ed got to thinking too much a while back....
In an effort to get maximum spark to the plugs, I got to thinking that since the Blaster II doesn't require an external resistor when used with electronic ignition, I'd replace the stock ballast resistor (or even eliminate it).
I experimented with different rated ballast resistors, took a bunch of meter readings at the coil for voltage reaching it, all that "thinking too much" stuff.
Currently, I have a ballast that is rated to damn near nothing (like 0.4 ohms) on the car, trying to get the full 12VDC through the system.
In the end, I don't think it made that much difference either way.
BUT....
Have I negligently caused possible harm (or at the least, messed with) the function of any OTHER parts of the ignition system in doing so?
What about the Mopar ECU? Does it matter what voltage gets to it?
Anything inside the stock distributor affected by what I've done?
Reason I ask is I'm chasing down a slight "jittery" run condition under very light load, low RPM conditions (say, going down main street at 30mph at like 1700RPM) where the engine can be felt just ever so slightly doing a little jittery "dance".
(The same situation can be almost imperceptibly observed sitting still and revving the engine gently above 1500RPM or so, up over 2000RPM). There's tiny little half-assed jitters going on.
NOT actual misfires or anything like that and the condition can be quickly overcome with more throttle and/or load applied; further, when the car is accelerated, there's no issues and all functions like it should.
Am I chasing after minutiae here? Does the ballast have anything to do with this?
Does anyone know what the rating of the ballast resistor sold in the Mopar conversion kits was/is?
