M/P Voltage Regulator Yes or No?

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2fine69s

2fine69s

69 340-6pak Rag Top
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Hey guys,
I have a Mopar Performance #P3690732 voltage regulator. Can I use this as a street application, or does it flow too many volts for a street car. I have a 372 ci, 6 pack engine with 469 hp but the electrical harness is all repo to oem specs. The altenatior is oem 69 vintage. Any help would be greatly appreciated,
Martin
 
Just a couple more peices of information....
The harness was fabricated for electronic ignition and I will be using the orange box.
Martin
 
If it's the blue regulator I would not use it for street duty, I have one on my duster and it really cooks the battery. Had a maintenance type battery and got acid all over the place.
 
Man I really appreciate this information, I've never run one of the blue regulators and was just not sure. Guess I'll just sell it. You Guys in FABO are the best,
Thanks Haze,
Martin
 
The only difference between this and a regular regulator is that this one is completely epoxy coated, which isolates it from ground, which means the alternator is essentially full-fielded. Running it that way for more than 1/4 mile at a time will indeed cook things. To use it on the street, just wirebrush or scrape off the blue epoxy from the mounting tabs so you get a good ground.

And there's no such thing as a voltage regulator that "flows too many volts". The voltage regulator is a control device for the alternator's field circuit, not a throttle valve.
 
The Mopar Performance regulators maintain a constant 13.5 volt output and will definetly overcharge the battery on a street driven car. An ungrounded regulator will not full field an alternator, you have to ground the regulated side to go full field.
 
skykeith said:
The Mopar Performance regulators maintain a constant 13.5 volt output
Click to expand...

Right, right, I can quote the MP catalogue too. :roll: This blurb is one of many factual errors to be found in that book. Fact is, all voltage regulators work to maintain line voltage at their setpoint, which on a "12-volt" system at 80°F ambient temperature is about 13.5V. Higher at lower temperatures, lower at higher temperatures. The operational theory is really simple; it's kind of amazing how many people so fundamentally misunderstand it.

Talk all you like about what you think an ungrounded regulator can and can't do; fact -- in the real world of metal and electrons and such -- is that all the OP has to do to avoid spending money on another regulator or spoiling his battery is provide the regulator with a good ground.
 
2fine69s said:
Hey guys,
I have a Mopar Performance #P3690732 voltage regulator. Can I use this as a street application, or does it flow too many volts for a street car. I have a 372 ci, 6 pack engine with 469 hp but the electrical harness is all repo to oem specs. The altenatior is oem 69 vintage. Any help would be greatly appreciated,
Martin
Click to expand...

When going to electronic iginition on 69 and earlier cars,this is the way to go.
I would have no problem using one on a street car. People use them all the time.
 
Sometimes I wonder if --The-- Great-- suffered a brain injury as a child.

As yourself this question? If the damned thing is coated in epoxy paint, and needs to be grounded, why in hell would you NOT simply clean the paint off -THE SAME WAY you would do with any painted regulator, and bolt the thing down?
 
Simply put: the electronic regulator is the ground connection for the alternator. Dual field alternators have 2 brushes that have terminals on them. One supplies power from the harness (~12V) and one takes it out to ground (The regulator, to complete the circuit) If the regulator is completely isolated from ground (the case is usually the ground to the firewall) There is no closed circuit to energize the alternator. The regulator varies the ground to its own case internally to maintain the ~13.5V output. If you run the GND terminal straight to ground in a dual field alternator, your alternator is going to put out more than your battery can safely buffer, and it s going to heat up and possibly boil over. The old 1 field alternators had the GND brush grounded the the alternator case, but the power into the alternator was regulated by the old points type regulator, basically "full power" until it reached a certain harness voltage, then it opened itself and ran on a high value internal resistor. Did this off and on to regulate the voltage.
If the MP regulator is "insulated" then it has to have an external ground wire. My guess is that its not fully insulated but regulates to a much higher voltage level than a stocker.
 
Why does my VR keep my voltage at the batt at 14.5 or so? this is a solid state wells replacement.
 
EL5DEMON340 said:
Why does my VR keep my voltage at the batt at 14.5 or so? this is a solid state wells replacement.
Click to expand...

14.5 ain't all that bad. The big problem with overvoltage with these old girls is "voltage drop across the harness." I've posted this before, here it is again.

As you draw current through any circuit, if the EFFECTIVE wire size--the resistance-- is large enough, you'll have voltage drop. How much "depends."

To see what YOU have, do this:

Get the battery charged, make these checks first with all accessories off, and again with the radio, heater, on. Run the car and adjust the idle to simulate "low to medium cruise."

Take your multimeter and stab one probe directly onto the battery negative terminal. Stick the other probe directly onto the regulator ground (frame of the regulator.) You should read a VERY low voltage, the lower the better. Zero volts is perfect, anything over .2V (two tenths) means you have resistance in the ground circuit between the regulator and battery neg. and need to improve things.


Now check the same thing on the positive side of the harness. On a "stocker" (wiring), generally, you have the path from the battery, to the starter relay, the fuse link and through the (troublesome) bulkhead connector, through some wiring and the ammter, to the ign. switch connector, through the switch and back out it's connector, and back out the bulkhead on the dark blue "run" (ign1) wire.

Ok, so stab one probe directly onto the battery positive post. Stab the other probe as close as you can get to the regulator IGN terminal, or on the blue wire going to the coil ballast.

Once again, same as the ground circuit, you are looking for a very low reading, and I WILL BET that there will be some drop in this circuit.

To find out where it is, just "chase" it back. Try one probe (probably need an extension) in the bulkhead connector, clip the other onto the ammeter, and so on.

On mine, which I barely got running with the "interim" (junkyard) 360, there is nearly a one volt difference. The wiring harness came out just yesterday!!
 
i had a powermaster 75 amp use to charge at about 14 volts running 2 fans and an electric fuel pump . it was fine until the neutal switch wire burned on the header and shorted out . i cant get the thing to charge over 13.2 then the regulator over heats and fails . of coarse some one changed the wiring at the fuse block and i dont no what the hell is what perhaps a new extenal wiring harness would help me. you guys are a wealth of information.
 
pishta said:
If the MP regulator is "insulated" then it has to have an external ground wire. My guess is that its not fully insulated but regulates to a much higher voltage level than a stocker.
Click to expand...

Your guess is a guess.
My experience is experience.

Just sayin'.
redbeard.gif
 
Your guess is a guess.
My experience is experience.

Ah, yes, more pearls from the "god of gods" (lower case not accidental)

WHY IS THIS SUCH A TECHNICAL ASSBREAKER??? Just scrape/ grind some of the God Dammed paint off the mounting and screw it DOWN!!!!
 
Took off my blue reg before I read this and spoke to Martin/2fine69s...

I had issues with headlites dimming at lo idle and someone recmnnded the blue reg. Then "heard" it wasnt good for daily driver so I put on the VR128 and now she jumps to 16v when accelerating. Thinkin about grindin down the back of the blue one and puttin it back on. btw - I did convert to elect ign.

See thread link:

http://www.forabodiesonly.com/mopar/showthread.php?p=1763696&posted=1#post1763696

http://www.forabodiesonly.com/mopar/showthread.php?t=173673
 
Johnny Dart said:
When going to electronic iginition on 69 and earlier cars,this is the way to go.
I would have no problem using one on a street car. People use them all the time.
Click to expand...

X2, been doing this for over 5 years and no issues, I also run an optima red top battery, no acid leakage for me...
 
67Dart273 said:
Your guess is a guess.
My experience is experience.

Ah, yes, more pearls from the "god of gods" (lower case not accidental)

WHY IS THIS SUCH A TECHNICAL ASSBREAKER??? Just scrape/ grind some of the God Dammed paint off the mounting and screw it DOWN!!!!
Click to expand...

You 2 guys are rather comical at times. Sounds like you're both agreeing you need to ground the darn thing. I don't see how it can work without grounding it.
 
cudajim said:
You 2 guys are rather comical at times. Sounds like you're both agreeing you need to ground the darn thing. I don't see how it can work without grounding it.
Click to expand...

No, I'm the one who said "just ground it." HE made it sound like a big deal

I'll say it again. I'd love to get one or two of these for a reasonable price to do some testing and blow up the hype (or not) once and for all.

There are enough guys who claim to successfully run them that I tend to believe they work just fine.

Friend of mine ran one of these long before Al Gore invented the internet, soon after MP performance lept onto the public scene.

Several dealers were our worst enemy. "Well, we'll ORDERrrrrrrrr it, but you have to PAY CASH FIRST and NO RETURNS!!! ('n sniff' we don' doin' it, garble, *****, moan.)

I finally told one parts guy, "If you think I'll ever buy a new Mopar from you guys after the crap I've put up with tryin to order parts, you might want to think about that."

If all it takes is scraping off a minute bit of paint, and you can't be bothered, then, well........................


Let's not forget other replacements are ALSO painted or chromed. Ya hafta' get a ground on them too!!
 
Once its grounded its grounded. done deal. The bigger issue is that the Voltage regulator needs to see that both voltages from the ignition and the field are the same. If not then the regulator will turn itself off and act like it is burned out periodicaly or fluctuate volage. Bottome line. Source the regulator's ignition voltage from a good clean source not interupted by a possible weak ign switch or such.
My voltage is 13.7 solid from idle on.
 
SebastianSpaghetti said:
. The bigger issue is that the Voltage regulator needs to see that both voltages from the ignition and the field are the same. If not then the regulator will turn itself off and act like it is burned out periodicaly or fluctuate volage. .
Click to expand...

You were doin' fine until you got here. The field voltage is a control element, and it's "voltage" has nothing to do with the IGN voltage which is in fact the sense. The only time the "field voltage" is going to be the same as IGN is when the regulator is turned off, in the case of an isolated field (the regulator controls the "amount of ground" on that leg), or in the case of the early 69/ earlier unit, if the field and IGN are the same, then the alternator will be at max output, "full field" in other words.
 
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