MAD electrical upgrade for 1973 Dart

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OwdKasd

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I am getting ready to do the MAD upgrade. My dart has an MSD 6A ignition unit installed and everything was working fine until:

1. My Dart wouldn't start and the Key would not engage the Starter.
2 I left the key in Run and jumped the Starter Relay but the car would not start.
3. The Fusible link started smoking at the Firewall so I disconnected the Battery.
4. I now have a Short to ground somewhere possibly the ignition switch.
5. So confused and don't know where to start. I figure if I start by doing the MAD upgrade first and then diagnose the ignition switch.

Questions
#1: Do I even need the Red wire in the Mad diagram when bypassing the Amp meter? It seem redundant.
#2: Can I just go directly from the Alternator to the Lug on the Starter Relay or are there other important wires along the path of the original wire.
#3 Am I correct that it is all connected to the same lug on the Starte relay?
#4: Is the Ballast Resistor needed with the MSD 6a. It was always pretty hot.
 
I just did this... Yes, you go direct from the alternator to the relay lug. This greatly reduces the load on the bulkhead connector and is a good thing!

I bypassed my ballast, but I am running a Pertronix II. I am using their coil also for the low resistance needed to get 12 volts to the system. The other feed uses a fusible link too and it is EASY to connect the ammeter wires together.

One thing to check (Don't ask how I know!) is that when you turn the key the 12 volts for starting comes from a different wire than the volts for running. There is S1 and S2 terminals on the starter switch..
 
this reminds me of when I pretty much rewired my entire engine bay after a short fried everything from the alternator to the steering column.

Del helped me every step of the way, and I'm betting he'll chime in here.

I think you may want to find the short before doing any modifications though, just from my experience.

How are the connections at the bulkhead connector?
 
Just did mine this weekend.. I just put both lugs on the ammeter on one post. and got rid of the firewall connections. I havent ran the alt direct to the starter relay yet.

Anyway I am running a MSD 6al also, Mine is being triggered by a unilite so it requires the ballast resistor. MSD has a lot of drawings out there for how to wire it up depending on your distributor. Likely your ballast was hot due to whatever short happened at the firewall or ignition switch.
 
this reminds me of when I pretty much rewired my entire engine bay after a short fried everything from the alternator to the steering column.

Del helped me every step of the way, and I'm betting he'll chime in here.

I think you may want to find the short before doing any modifications though, just from my experience.

How are the connections at the bulkhead connector?
Thanks, The conections are crappy especially where the Fusible link fried. That was where the Red wire runs to the Amp Meter. I will find the short before hooking the Battery back up.
 
Ballast is not required on an MSD 6 box. The wires from original ballast to MSD only turn the box on. You can leave it in series, but, it's not necessary.

The mad deal gets rid of the black charge wire and red power wire from the relay lug bypassing the bulkhead. If you want to run a fuse link, I put it attached to the relay lug and have two wires (alt wire and relay lug) travel into the car attaching to the existing black and red wires inside.
 
Just did mine this weekend.. I just put both lugs on the ammeter on one post. and got rid of the firewall connections. I havent ran the alt direct to the starter relay yet.

Anyway I am running a MSD 6al also, Mine is being triggered by a unilite so it requires the ballast resistor. MSD has a lot of drawings out there for how to wire it up depending on your distributor. Likely your ballast was hot due to whatever short happened at the firewall or ignition switch.
Okay thanks, I wasn't sure if the Balast resistor was normally hot. I really appreciate the replies on this as I am pretty poor at electrical/wiring. The MSD system was in the car when I got it but I will try to compare the wiring to their website. I also need to ID the distributer.
 
Ballast is not required on an MSD 6 box. The wires from original ballast to MSD only turn the box on. You can leave it in series, but, it's not necessary.
Okay thanks, Is this regardless of what type of distributer is installed? Does it being extremely hot indicate a short?
 
The resistance generates the heat. They will get blister your finger hot even with stock ignition. That's why they are in a ceramic casing and why they are mounted separate from flammables.
 
I Got the wiring upgrade done. There's definitely a dead short in the ignition switch. I will order one and take it from there.Thanks for all the replies so far.
 
Do I need to ground the ignition switch for test purposes? I have it hooked up but not installed in column yet. Short is gone but it will not engage the starter in the start position. Thanks. Also 2 more weird points:

1: There is power to the Starter Post on the starter relay even when in run position(Not Start pos.)

2 There are 2 empty "slots" on the pigtail of the new Ignition switch which are occupied on the old switch. They are on the very end and they are red. the wires they connect to on the other side are black.
 
Update: I am able to run the car by putting ignition switch in run position and then jumping the Starter relay.
If I turn ignition switch to start, I get power to both of the lower terminals on the relay. but power is not going to Starter Lug on relay. It is starting to look like a bad starter relay.
 
So, I traced the wire that goes to the neutral safety switch. The 3 wire plug is not even hooked up to the Switch on the Trans. Previous owner must have grounded it somewhere and after moving things around the connection got fixed. So now I can start it with the ignition switch. Now I just need to repair the wiring for the Neutral safety/Back-up light switch and install the Ignition switch into the Steering column. After reviewing th ewiring diagrams, I can't even see how the Signals/Reverse lights are even working.
 
Sounds like you are doing a pretty good job there. Does this car have an aftermarket shifter? If so, some have a backup switch contact inside of them.
 
So, I traced the wire that goes to the neutral safety switch. The 3 wire plug is not even hooked up to the Switch on the Trans. Previous owner must have grounded it somewhere and after moving things around the connection got fixed. So now I can start it with the ignition switch. Now I just need to repair the wiring for the Neutral safety/Back-up light switch and install the Ignition switch into the Steering column. After reviewing th ewiring diagrams, I can't even see how the Signals/Reverse lights are even working.

Wait! I have a Hurst shifter that is currently being installed I have not hooked up the shifter yet. I have the gear in park and the safety switch installed but I do not have any electricity going to the shifter because I am not sure how to wire it just yet. Now that I think about it I may have had my car in N when I cranked it and I got backfire.
 
I wish I knew how to test electrical under the hood! There are no step by step instructions out there on how to do this. Maybe I bit off more than I can chew. I know some stuff but this is more of a learning thing for me. I assumed it would go a heck of a lot smoother.
 
I am getting ready to do the MAD upgrade. My dart has an MSD 6A ignition unit installed and everything was working fine until:

1. My Dart wouldn't start and the Key would not engage the Starter.
2 I left the key in Run and jumped the Starter Relay but the car would not start.
3. The Fusible link started smoking at the Firewall so I disconnected the Battery.
4. I now have a Short to ground somewhere possibly the ignition switch.
5. So confused and don't know where to start. I figure if I start by doing the MAD upgrade first and then diagnose the ignition switch.

Questions
#1: Do I even need the Red wire in the Mad diagram when bypassing the Amp meter? It seem redundant.
#2: Can I just go directly from the Alternator to the Lug on the Starter Relay or are there other important wires along the path of the original wire.
#3 Am I correct that it is all connected to the same lug on the Starte relay?
#4: Is the Ballast Resistor needed with the MSD 6a. It was always pretty hot.

Now when I was trying to start mine I had smoke but... I was inside trying to start it so I dont know where it was coming from. It was down by the passenger side near the exhaust headers. I had however just filled up my tranny fluid and I know some spilled but nothing would have been hot enough to burn the oil since the dang thing would not start anyways. I think I am going to start looking for some fried wires somewhere.
 
Sounds like you are doing a pretty good job there. Does this car have an aftermarket shifter? If so, some have a backup switch contact inside of them.
Thanks, The shifter is in the column. But at one time before I got the car, it had a floor shifter. Some mods were definitely done to the wiring. right now everything seems to be working fine. It will be pretty hard to find the "Jump" to ground. I haven't had a chance to see if it will start in drive or if I have reverse lights.
 
Car will start in any gear position. No reverse lights. I need to figure out what the prev owner did to bypass the neutral safety switch circuit and fix that. Then hook up the neutral safety switch. That should get me reverse lights.
 
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