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Need some help with 68 Charger wiring

AA1 68 R/T

Well-Known Member
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4:25 AM
Dec 8, 2022
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Looking for some help in the electrical area on my newly acquired Charger. Someone has done a pretty poor job with some wiring they have done and I need to clean some things up. 68 440 Charger. They tried to wire up a newer factory ecu with a 4 prong ballast. There is a new voltage regulator and a new alternator but not sure if they are correct. They do not have the alternator connected and with some of the additional wiring they have added on the car it scares me to connect it lol. The car will start but I think I will be removing ecu and ballast to go another direction. Electrical on Mopars is not my strong point lol. Here are a few pictures of the alternator and voltage regulator. Thank you for any help you can provide.


From what I can see it appears the insulating washer is not on the field connector you show so, it seems to me that all is correct. As long as one field terminal is fed from the regulator and the other is grounded, a later model alternator will work.

Are most mopar alternators and voltage regulators compatible/interchangeable ? I need to take this alternator off when I was looking at the back of it it looked like it had 3 tabs on it plus the stud for the bigger wire.
I’ve been reading some posts on here and scares me when I read about voltage regulators start smoking lol
Shouldn't the square back alternators use the newer style voltage regulator?
Not all square backs these days are for the newer style regulator. Many of the rebuilds out there use the square backs because of the lack of roundback casings from what I understand. So they rebuild a square back with one field terminal grounded(and clipped) for ‘69 and older. When they rebuild them for ‘70 and newer, both field terminals are usable and “not-grounded” as they should be. Looks like you’re using the ‘69 and older style VR here, so (1) terminal on the alternator should be grounded and not used. The grounded alternator terminal is often accomplished by a metal washer being installed between the terminal and the case.
The squareback alternator comes with two field terminals, while the original '68 roundback would only have had one. This later alternator will work fine with the pictured voltage regulator if one of the terminals is grounded to the case. Looking at your picture of the alternator, the field terminal shown should be grounded to the case. The later squareback alternator typically had a higher amp. rating than the earlier piece.
The squareback alternator comes with two field terminals, while the original '68 roundback would only have had one.
But there are roundback alts with two fields terminals, used on 70 and 71s since squarebacks appeared on 72 while the electronic regulator floated on late 69 for big Chryslers and fit on all bodies by 70.

Just saying this because we can’t say every roundback is single field, so need to be checked first. Sure the original one on 68 was single field.
This is a dual field roundback alt with also the provision for the single field grounded brush. Mostly sure used as a replacement to be set up for the needs


While the tipical dual field roundback alts coming out from assembly line used on 70/71 look like this

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I don’t mean to hijack but I’m having a problem with my 66 charger with a 383 it has a Holley sniper electronic ignition electronic voltage regulator my ballast has a wire in it connecting for the sniper hot wire. My alternator is a 2 field and it looks ad is the one brush doesn’t have a rubber o ring under the head of the bolt. My 1 field wire (green) is hooked up to the one with the o ring. My battery reads 12.6 and alternator stud is the same off. When it’s running they still read the same but start to drop .01 continuously the furthest I’ve let it go is to 10. My system is not charging and I don’t know what to do. If any expert in this dodge system would message me I’d really appreciate it. This is my last hurdle and I can finally enjoy my car thanks in advance.
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