It looks like the PCM only controls the field windings on the alt..... Don't know what the wiring diagram looks like on the 78.... it 'might' work just fine....

 

If I could figure out how to link one page of my pdf manual for the '78, I would show you exactly what it looks like, unfortunalty, its not working out. I tried doing a "print screen" then save it to paint and attatch that, but my print screen button doesnt appear to do anything.

 

Alt+Print Screen copies the active window, then you can ctrl+v into paint. Host it somewhere like photobucket, then link to it here.

 

http://i1288.photobucket.com/albums/...ps0d6ccb68.png AH HA! You the man!

 

Wow. I miss the days when things were simple.......

You can do it either way, use the current system to control the alt, or, just hook the right wires to the right spots on the alt, and have the PCM control it. Leave the wire for the ammeter hooked up, and you should be golden.

 

if you leave the amp gauge hooked up it would work to a certain degree but there are so many electrical upgrades that you should do that it would not really do much even if it was hooked up. when i say upgrades i mean putting thing like headlights, backup light, wipers, blower motor all on relays. then the things that draw any major load will get as much power as they want.

 

As you already know, earlier Dodges werent exactly known for thier steller charging systems, so I believe I will use the PCM to control it. I will be putting all of my heavy load items on relays. So if I understand what you guys are saying, I can use the PCM to control the charging system, but leave my ammeter hooked up as if nothing changed?
Also, I have a few extra db/bk sensor ground wires now that I thinned the harness down. Figured it never hurts to have an extra ground wire. Any reason I cant tie my Park/Neutral sense wire into one of these so that the PCM will think its in neutral and allow it to start?

 

i would probably just have used the pcm to control the charging system just to keep things simple and clean. now i am not saying throw out the old voltage regulator system. those 2nd gen trucks like to quit charging sometimes and the only way to go is old school voltage regulator. they work good as long as they have good connections.

extra grounds are always good. i try to ground as much to the battery as possible. i am not quiet sure how the park neutral sense wire works on the 2nd gen trucks but i would guess you could hook it up and try. if it works you are good. if not you will have to figure out what went wrong.

 

I am using the PCM to control charging. How do you suggest keeping the voltage regulator as well as run the new system through the PCM? Doesnt the new alt style have a built in regulator?

The Park/Neutral Sense wire just needs to be grounded to tell the PCM its "Ok" to start. Hopefully using one of the previously used sensor grounds isnt an issue, being as I've already soldered, shrink tubed and wire loomed it all back together. It is starting to look like a stock harness again.

 

i was more so thinking don't throw it in the trash. keep it in the tool box just in case it quits working. i am pretty sure most dodge vehicles have external voltage regulators. makes the alternators cheaper and easier to work on.