wiring the MSD 6a

[AmadeusCharger500]

Can anyone give me a breakdown of how to wire the MSD ignition box? I currently have an electronic distributor with an FBO ignition.

Thanks

[original72]

actually pretty easy to wire..... the thick red wire goes to the BATT positive and the thick black to the BATT negative..... the thin red wire goes to a switched 12 volt source so hook it to either side of the ballast resistor... doesnt matter which since all it does is act as a switch to turn the box on and off..... orange and black wires get connected to the coil.... orange to positive and black to negative.... since you have a electronic distributor you will be using the purple and green wires to trigger the MSD box..... here is a link to the MSD site with a page to download the full instructions...

http://www.msdignition.com/downld1.htm

[AmadeusCharger500]

What happens to the blue wire coming from the key into the "in" side of the ballast? Is that the battery positive or do you hook directly to batt. If so, run a separate wire from battery? Can the black just hook to a good ground? Does it have to connect directly to battery?

[John_Kunkel]

There's a problem if you use the blue wire on the ballast as the MSD switched source because the blue wire shuts off when the key is in the Start position. The best way is to eliminate the ballast and hook both of the ballast wires together, this will assure a 12V source in both the Start and Run position.

The large red wire can be hooked either directly to the battery positive terminal or the large terminal on the starter. The large black wire can be hooked to the block at the same bolt that attaches the negative battery cable.

[AmadeusCharger500]

Do you mean to remove the ballast and simply connect both ends with a jumper wire and additionally add the thin red wire into those?

What other options for the battery positive wire? Can the big red wire be connected to the thinner of the two postive battery wires at the terminal ending on the starter relay? Perhaps that is what you meant by hooking it to the starter otherwise wouldn't it be quite a hassle trying to hook it on the the starter stud?

[John_Kunkel]

Do you mean to remove the ballast and simply connect both ends with a jumper wire and additionally add the thin red wire into those?

Yes.

What other options for the battery positive wire? Can the big red wire be connected to the thinner of the two postive battery wires at the terminal ending on the starter relay? Perhaps that is what you meant by hooking it to the starter otherwise wouldn't it be quite a hassle trying to hook it on the the starter stud?

I wouldn't hook it to the relay. I suggested the starter because it's out of the way and looks better; if you don't mind extra wires attached directly to the battery terminal, hook it there.

[myk]

So, we don't need the ballast resistor?

[bill440rt]

I have mine hooked up in my '68 that way. I bypassed the ballast resistor, but left it on the firewall & "dummy wired" it into the harness. That way, it still looks stock.
I also hid the box under the driver's seat, & ran the harness thru a non-used plastic grommet in the lower area of the firewall. You'd never know it was there.

[AmadeusCharger500]

I guess we don't need it with the MSD. I assume the MSD box just works fine with the 12+volts from the battery and needs no voltage drop.

One more question though. What to do with the plugs on each side of the ballast. I have a New engine harness and darned if I am going to cut those plugs off. So I Made up a spade connector that would link the 2. Is it possible to leave the ballast on since that wire is just acting like a switch anyway. The whole point of my changing to MSD box and coil was that my ballasts were being burnt by the system I bought from FBO. But if I can keep it just for looks that would be fine.

[AmadeusCharger500]

Well its all hooked up and car runs fine. New dilemma though. The MSD coil has a longer input tube than the standard coil I was using. My coil wire does not reach that far down into the coil. So were do I get the proper coil wire. I am just using a standard set so I assume MSD needs either their own wire or some special end for stock wires.

[bill440rt]

Uh....
You should be able to slide the boot up a little bit on the wire, giving you a little extra.

[AmadeusCharger500]

Thank you. That thought had occurred to me, but only after some down time from the car.

[myk]

Quick question here.  Am I correct in understanding that if you have an electronic ignition, like the Mopar Performance electronic conversion kit installed along with an MSD, you don't need to use the ECU?  According to the MSD installation instructions, on page 16: http://www.msdignition.com/pdf/6%20series/6series.pdf it says to leave the "Chrysler module disconnected" and I'm assuming they're refering to the ECU?

Right now, I've got the orange box ECU and the MSD 6 installed.  If it turns out the ECU didn't need to be hooked up all of these years I'm gonna' feel really dumb.  What problems or performance issues could I be having with both of these hooked up?

[Ghoste]

You are correct that you no longer need it, the MSD is the ECU in their case.  No need to feel dumb though, their instructions aren't the clearest.  As for it's affect, I have no idea but your car still seems to be running so...?

[myk]

I'm glad I'm not the only one who sees it that way.  Jeez I can't believe it.  I'll look into splicing that connection today.  Do any of you guys have a similar setup?  I guess I'm shocked that the car would run with both the MSD and the ECU hooked up.  You would think that the signals would get crossed and keep the car from running properly, or something.  Or, maybe it's been running wrong all of this time...

[Ghoste]

I'm no electric guy but my guess would be that if anything it likely didn't affect it much.  I still have my MP setup under the hood wired up and ready in case of a problem with the MSD.  I can just swap a couple of connectors and be back running under the old system.  Not because I'm expecting a problem with the MSD, just because it was easy to do at the time.

[Mefirst]

This topic has been discussed many times, use the "Search" button... But here is a wiring diagram how you hook up the MSD system...



/Tom

[myk]

That's a helpful diagram that helped me wire my dual field 'alt, but it makes no mention of the ECU, hence my question...

[Ghoste]

Conversely though, it makes no mention of it because it isn't used.