Electronic Ignition Ballast Resistor

[70charger2006]

I was wondering if someone could post a few pictures of the mounting location of a 4 prong electronic ignition ballast resistor? My car was originally a regular point ignition and I have since upgraded it to electronic. I already have the correct 4 prong ignition but it seems that it won't mount to the original location of my old one. Is there a difference on where the hole is in the firewall to mount the two different resistors? This is on a 70 Charger. Thank you in advance.

[ODZKing]

Not sure if this is going to help you.  Third gen's have to bars from fenders to fire wall.  This is a 73.

[Back N Black]

Here is a couple pics of my charger.

[70charger2006]

Here is a couple pics of my charger.

Is that the stock location of your resistor or did you have to drill a new hole? I have an A/C car and my water valve is right where your resistor is located.

[ODZKing]

From pics on the internet, looks like the stock position is just above the valve.  But the dual most likely won't fit, it only has enough room for the single.

http://www.mervsclassiccars.com/70_charger_engine.html

Any reason why you're using a dual?

[70charger2006]

From pics on the internet, looks like the stock position is just above the valve.  But the dual most likely won't fit, it only has enough room for the single.

http://www.mervsclassiccars.com/70_charger_engine.html

Any reason why you're using a dual?

I upgraded the engine harness to an electronic ignition harness from year one and it requires the use of the 4 prong ballast resistor.

[Chryco Psycho]

if the ECU is a 4 prong unit as most are using a 4 prong ballst is a waste of time you still only use the coil feed wire off of the ballast 

[maxwellwedge]

I was wondering if someone could post a few pictures of the mounting location of a 4 prong electronic ignition ballast resistor? My car was originally a regular point ignition and I have since upgraded it to electronic. I already have the correct 4 prong ignition but it seems that it won't mount to the original location of my old one. Is there a difference on where the hole is in the firewall to mount the two different resistors? This is on a 70 Charger. Thank you in advance.

You can mount it wherever you can - No 70 ever came with a dual ballast resistor.....Chryco Psycho is right though - wire it up for the normal single ballast resistor.....don't ask me how, but I am sure someone will pipe in.....

[Chatt69chgr]

I ordered the same "upgrade" engine harness you did from Year One.  I did note what they said about the 4-prong ballast and that their wiring "requires" the use of said ballast.  From what I've read, the 4 prong ballast was used with a 5 pin ECU.  The 4-prong ballast is actually two ballast resistors in one block.  One of the resistors performs the ususal function of lowering the voltage to the coil to approximately 9 Volts in the RUN position on the starter switch.  The other resistor was used to lower the voltage to the ECU when a 5-pin ECU was used.  Now if you are using a 4-pin ECU, then you would not need that function as it were--the 4-pin ECU doesn't need it's supply voltage to be lowered.  Your next question is going to be, what do I do with the extra two wires.  I would think that if you trace them out that one would come from 12 V and the other would probably go to the pin that goes to the 5th terminal on the ECU----the one you don't have if you are using the ECU that most are using (lthe 4-pin).  So if this is the case, then you would just tape those wires up in the harness, insulating the terminals so the 12 V one is not shorted out to ground, and forget about them.

This is how I THINK it works.  I may be wrong.  Could someone confirm what I've said or tell me what what should be done.

[Budnicks]

Mine is mounted like Back N Blacks or very similar,  I used the Year one engine bay electronic ignition upgrade for a 68 RR harness also, it worked great, I did do minor alterations for my own installations... If I remember correctly it's 73 & later that use the 4 prong ballast & the 5 pin ignition modual, don't quote me on that I'm just going from memory.... You can check out the schematic on MyMopar.com

[ODZKing]

See if this is helpful.
http://www.retrorarities.com/EIconversion.htm