wiring an Msd ignition

[71_deputy]

I reread this thread over again.. and I still don´t understand why you would bypass the ballast resistor. The thing that makes me most confused is that one of the FLD wires from the alternator is also connected through the voltage regulator to the ballast resistor (blue wire side).

BALLAST RESISTOR IS ONLY FOR THE ELECTRONIC MOPAR IGN. THE BLUE WIRE CONTINUES OVER TO THE VOLTAGE REG.- IT DOSEN'T HAVE ANY BEARING ON THE REG.

If you remove the ballast resistor, where do you connect this wire then???
USING THE ENDING POINT OF THE BLUE AND BROWN CONNECTORS- CUT THEM AND SPLICE TOGETHER AS WELL AS ADDING A WIRE FROM THIS POINT TO FEED THE SMALL RED WIRE TO THE MSD.

and how will that effect the function of the cars electric system..    NONE


I just don´t buy this way of wiring up and MSD box. If this was the way to wire the box, MSD would have put it in print in the user manual for the ign. box. But al it states is to take power to the "little red" wire from the original coil + wire, which in the Mopar electric system is the brown wire, NOT the blue.. 

THEY ARE NOT PERFECT! THE BLUE HAS +12 VOLTS ALL THE TIME AS THE BROWN ( POWER IS NOW THRU THE BALLAST RESISTOR ) CAN BE AS LOW AS 7-8 VOLTS- THIS MAY NOT BE ENOUGH VOLTAGE FOR THE MSD ( ESPECIALLY IF YOU ARE IDLING- VOLTS COULD BE THEN AROUNG 5-6 ) AND IT MIGHT SHUT DOWN .

Id like some closure to this and you guys who wired your car by splicing the blue/brown please explane why and what the benefit would be to wire it up like that, an further where did you make the splice between the wires and did you loose the ballast resistor al together...
CHECK ABOVE RESON WHY- IT COULD SHUTDOWN!


USING MSD DOSEN'T REQUIRE A BALLAST RESISTOR- SO IT CAN BE REMOVED

[firefighter3931]

I reread this thread over again.. and I still don´t understand why you would bypass the ballast resistor. /Tom

Tom, the ballist resister can be removed because it's no longer required for voltage spike protection. The ballist resisters are known to fail so removing it means one less thing to go wrong. I've allways connected the two wires together (blue/brown) when installing the MSD....no problems. I've done a half dozen like this over the years, fwiw.

Ron

[dodge freak]

I like to add that the GM and Ford cars do not have a resistor. I think msd is just making it easier for somebody to add it to their car. Like I said call them up and speak with them, they know alot or they would not be answering the phone. I'm sure others have asked the samething so they may be able to explain it better.

[Mefirst]

OK.. Now I see the light, thanks Guys  

Well the ballast resistor is going -Bye, bye...

*** One more thing. The wire that comes from the the alternator Fld, the wire that goes between the voltage regulator to the ballast resistor, you skip that wire al together ?? I just want to make shore I got everything right before I do anything...

/Tom

Ps. I think this thread should be a sticky and later moved to a section for important threads (like the section we had in the old board) If someone could make a wiring diagram on how you hook up everything, this thread would be better than perfect

[firefighter3931]

Here's an MP diagram for wiring in the MSD Unit. 

Ron

[dodge freak]

Very nice diagram but the white wire that is marked not used can be use as a kill switch if its grounded there will be no spark so nobody can start it until you disconnect it from ground. What I did was run it to my trunk and put a on-off switch by my rear speakers and ran the other side of the switch to a good ground. Then if its park overnight or somewhere I feel its unsafe I open the trunk and flip the switch to the on postion. Now its harder for somebody to start. We could still cut that wire and start it but it slows a bad guy down.

[71_deputy]

Tom- you still need the blue wire to the voltage reg. for it to work correctly!!!!!!

[Mefirst]

Tom- you still need the blue wire to the voltage reg. for it to work correctly!!!!!!

Where do you hook it up when you loose the ballast resistor??? Do you wire the blue wire directly to the voltage regulator wire?

[71_deputy]

the wire that used to feed from the wire harness is dark blue with another one attached to it that goes to the old ballast resistor- they stay together- cut the old connector off, strip the wires, twist them, then cut the connector off the old brown wire that used to go to the other side of the ballast resistor, strip the wire and then twist it to the two blue wires, now take the new small red wire from the MSD box and twist it to the blues and brown.  solder the wires real good- sloppy or cold solder will not do- when you get them nice and hot- the solder will flow nicely. now the best way is to heat shrink the bare wires - tape in a juffy- but do the heat shrink!!!


John Mac

[Mefirst]

OK, thanks 

/Tom

[71_deputy]

your welcome!!!!

[my73charger]

 

This is a VERY helpful thread.  I am hooking up my MSD tomorrow so I thought I would do some research.

Thanks guys! 

[my73charger]

The blue wire that will be spliced into the brown and then into the red on the MSD also has a wire that runs into the voltage regulator and also one that runs into the alternator.  Do you leave these as is?

[Mefirst]

Here is a wiring diagram how you hook up the MSD ign. box...



/Tom

[gasoline_24]

Instead of starting a new thread I thought I would just continue on this thread.  I understand the final wiring diagram, but my 68 setup has a blue and brown wire going into one side of the ballast resistor and a blue and blue/yellow wire on the other side of the ballast resistor.  Just to be clear do all four of these wires get spliced together with the small red wire from the MSD box?  If not which blue wire (from which side of the ballast resistor) gets connected with the brown wire?  What happens to the other wires?

[John_Kunkel]

Yes, even though the previous replies refer only to a blue and brown wire there is actually a double blue on one side of the ballast and a blue/brown on the other side; tie all of them together when running the MSD and eliminate the ballast altogether.

If the ballast is required for original appearance, just jumper the two sides of the ballast.