4 Prong Ballast resistor?

[MykeNytemare]

Hello all,

I am almost ready to fire up everything, but as I install an MSD box on my 67, I am not sure what wires I need from the ballast resistor and I do not see a similar setup on the mymopar wiring diagrams I have found. It may help that my car's drivetrain had been changed to a mid/late 70s setup at some point before I go it.

Anyone have a 4-prong ballast resistor diagram or schematic for their vehicle that has that setup they can share?

Thanks for all the help and I will post a video of the startup soon once I get this done!

 

[Nacho-RT74]

do you have a 4 prongs ballast ? Did you get electronic ignition upgrade with 5 pins Mopar module ?.

Per MSD instructions the MSD box just need the old wire running to + lead of coil to the remote on wire to the MSD module. The ballast can be still there since they don't say to jump out or remove the ballast, just use the original coil wire the way it is. The low voltage going throught ballast is still able to turn on the module. Rest of wiring to MSD is independient from the existant wiring. You will have hanging out the old dist wire plug and old ECU plug.

 

[66Satellite47]

Neither of the MSD boxes I had used the ballast resistor. Check the MSD web site for the wire diagrams.

 

[Nacho-RT74]

I'm not saying it uses the ballast, just say the MSD modules instructions doesn't say need to be bypassed or removed, and just use the + coil signal just the way it is, because is just for remote on signal.

RTR distributors ( MSD and any other brands ) requires the ballast bypass thought and I think thats is mentioned just on those.

 

[66Satellite47]

The wiring diagrams do NOT include a ballast resistor in the wiring. + coil gets full 12V.

 

[Nacho-RT74]

the wiring diagram shows to conect to ORIGINAL + coil wire. Doesn't say anything anywhere around if is 12 volts or need to bypass the resistor. Doesn't even say "ignition switch" like the rest of diagrams.

The resistor is mentioned on manual to other optional applications ( run on or tach misread, pag 7 and 8 ).

 

[383man]

I have seen guys do it both ways as basically you are both right. I was always told that the MSD box should get 12 volts but as was said they don't show that on the wire picture and I know guys who leave the ballast in their cars and just hook the old coil + wire to the MSD box. Myself I always take the ballast out and run a full 12 volts to the MSD but I have seen it work with the ballast still hooked up. Course as many of us Mopar freaks I know which wires to hook up when removing the ballast so I always take it out and hook the J2 ign run wire and the brown ign 2 wire that's hot when cranking together to the MSD box. He can do it which ever way he wants to but I always feel better with the full 12 volts to my MSD box. Ron

 

[Nacho-RT74]

Well I'm not saying is wrong to bypass or modify the ballast. Is just matter of prefference, but would be false to say IS A NEED, because that's not mentioned anywhere.

RTR distributors effectivelly says 12 volts from ign switch, but not MSD module

 

[Curiousyellow71]

There have been several on the forum that were running the msd with the ballast in place. They had low spark problems and the fix was getting full voltage to the msd. Do yourself a favor and don't use the resistor with a MSD.

 

[66Satellite47]

Nacho, I choose to follow the MSD wiring diagram which clearly shows NO ballast resistor. But to each their own.

 

[Nacho-RT74]

Nacho, I choose to follow the MSD wiring diagram which clearly shows NO ballast resistor. But to each their own.

Let me know where it says no ballast resistor? I couldn’t find it!

 

[Nacho-RT74]

There have been several on the forum that were running the msd with the ballast in place. They had low spark problems and the fix was getting full voltage to the msd. Do yourself a favor and don't use the resistor with a MSD.

Doesn’t have sense to me because the load is not sourced by that wire. That wire is just to turn it on.

 

[Nacho-RT74]

Let me know where it says no ballast resistor? I couldn’t find it!

Nevermind, just found it. It doesn’t say NO BALLAST, just say is RECOMENDED bypass it.

but still there is not a diagram showing a ballast bypass or some statement making it as mandatory

 

[Rusty 72]

I run an MSD as well and I swear I've had to read those instructions about 6 times. You'd think they could word stuff a little better, and I feel like I have a good handle on things.
Glad you got it figured out.

 

[frumharlem]

I have seen guys do it both ways as basically you are both right. I was always told that the MSD box should get 12 volts but as was said they don't show that on the wire picture and I know guys who leave the ballast in their cars and just hook the old coil + wire to the MSD box. Myself I always take the ballast out and run a full 12 volts to the MSD but I have seen it work with the ballast still hooked up. Course as many of us Mopar freaks I know which wires to hook up when removing the ballast so I always take it out and hook the J2 ign run wire and the brown ign 2 wire that's hot when cranking together to the MSD box. He can do it which ever way he wants to but I always feel better with the full 12 volts to my MSD box. Ron

Hi, can you please clarify which wires you are saying need to splice to the thin Red MSD box ? Is it the Ignition 1 and Ignition 2 wires? I ask because I am trying to eliminate the Ballast Resistor on my 1971 Dart. I had two brown wires on the right side of the Ballast and I have 2 blue wires and 1 black wire on the other side. I ALSO have read other posts that go farther and say to also splice the Blue wire form the voltage regulator to the same thin Red wire to the MSD box.

So, I am confused...

 

[frumharlem]

There have been several on the forum that were running the msd with the ballast in place. They had low spark problems and the fix was getting full voltage to the msd. Do yourself a favor and don't use the resistor with a MSD.

Can you please explain how to eliminate? I have ran mine for 2 years with the Ballast. I want to eliminate the ballast, but not getting the wiring right. My ballast has 2 brown wires on the right (brown with white line) and on the other side is 2 blue and 1 black wire.

 

[Curiousyellow71]

Unhook the ballast resistor and find the wire that has power to it coming from the ignition. You should be able to connect your msd directly to that wire and remove the ballast resistor. I think its the blue wire. If there is two blues one may be for crank(ignition 2) and the other for crank and ignition (ignition one). You want the blue for both( ignition one). If the blues are hooked together then it should not matter whether ign 1 or 2 just hook the msd wire to it.
I think its the top of the ballast resister on the drivers side? It should be switched. Since your not running the factory electronic ignition none of the wires serve a purpose anymore other then switched 12v power coming from the ignition.

 

[383man]

Hi, can you please clarify which wires you are saying need to splice to the thin Red MSD box ? Is it the Ignition 1 and Ignition 2 wires? I ask because I am trying to eliminate the Ballast Resistor on my 1971 Dart. I had two brown wires on the right side of the Ballast and I have 2 blue wires and 1 black wire on the other side. I ALSO have read other posts that go farther and say to also splice the Blue wire form the voltage regulator to the same thin Red wire to the MSD box.

So, I am confused...

This wire pic may help you. Take the blue wire from the ign 1 on the ign switch and hook it together with the brown wire from the ign switch ign 2. You can unhook the ballast and not use it with MSD and splice the wires right there and then hook the same coil + wire to the MSD box that's 12 volts in the run and start position. Its easiest to just hook them together at the ballast connector because that blue J2 wire also supplies the alt field and voltage reg so you don't want to cut it at the wrong place. You can actually just jump the ign 1 and ign 2 wires (Blue & Brown) at the ballast and then hook the coil + to the MSD. Good luck and ask away if we can help anymore. Ron

 

[frumharlem]

3.

Unhook the ballast resistor and find the wire that has power to it coming from the ignition. You should be able to connect your msd directly to that wire and remove the ballast resistor. I think its the blue wire. If there is two blues one may be for crank(ignition 2) and the other for crank and ignition (ignition one). You want the blue for both( ignition one). If the blues are hooked together then it should not matter whether ign 1 or 2 just hook the msd wire to it.
I think its the top of the ballast resister on the drivers side? It should be switched. Since your not running the factory electronic ignition none of the wires serve a purpose anymore other then switched 12v power coming from the ignition.

So don't touch any wires on the Voltage Regulator?
I am confused on both because the MSD directions say that I am to connect the original wire that went to the Pos side of the Original MOPAR Coil to the thin Red MSD. According to the wiring diagram that would be the Brown, not Blue.

This wire pic may help you. Take the blue wire from the ign 1 on the ign switch and hook it together with the brown wire from the ign switch ign 2. You can unhook the ballast and not use it with MSD and splice the wires right there and then hook the same coil + wire to the MSD box that's 12 volts in the run and start position. Its easiest to just hook them together at the ballast connector because that blue J2 wire also supplies the alt field and voltage reg so you don't want to cut it at the wrong place. You can actually just jump the ign 1 and ign 2 wires (Blue & Brown) at the ballast and then hook the coil + to the MSD. Good luck and ask away if we can help anymore. Ron

View attachment 961131

RON THANK YOU!

I wish I heard your guidance last week! I now have CHOPPED SUEY going on under my hood : (
I already cut the blue wire about 3 inches from the voltage regulator. I cut bot brown wires coming off ballast. It's a rats nest that I created of jumpers and blue spade splicers!
Your picture of the alternator raises another question. One of the wires to the ballast goes to the Alternator.
I have a 4 connection Alternator:
1. Ground to block
2. Green Exciter to Voltage Regulator
3. A wire that goes to an L shaped connection on the top of the motor block, like a sensor of some type.
4. Black wire..... well that is going no where right now. I believe went to the left side of the ballast. I gotta figure out where that needs to go.


Last night I went to my 5 Pin connector that went to the original ECU/Ignition Module. There along with the wire diagram I have all the wires. I should have just jumped off of the wires right there in front of the 5 pin....right? The ECU is literally 1 foot from the MSD mounting location.
I think I also messed up when I replaced my bulkhead connector. I swear I payed attention and I xfered one wire at a time to the new one. But, I noticed that on my ignition switch harness, the yellow wire is always hot. Looking at the wire diagram I think instead of the yellow feeding the starter relay, it is mated to the Red Battery wire. This might explain why as soon as I turn the key the mail fuse blows!
I need to redo the whole middle plug of the bulkhead block.

 

[66Satellite47]

This wire pic may help you. Take the blue wire from the ign 1 on the ign switch and hook it together with the brown wire from the ign switch ign 2. You can unhook the ballast and not use it with MSD and splice the wires right there and then hook the same coil + wire to the MSD box that's 12 volts in the run and start position. Its easiest to just hook them together at the ballast connector because that blue J2 wire also supplies the alt field and voltage reg so you don't want to cut it at the wrong place. You can actually just jump the ign 1 and ign 2 wires (Blue & Brown) at the ballast and then hook the coil + to the MSD. Good luck and ask away if we can help anymore. Ron

View attachment 961131

Ron, fantastic diagram, easier to grasp than the FSM with pics of the Alt & VR. Thanks