Members Opinions and Comments on Today's Electronic Voltage Regulators

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RBConvert

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Before asking my question, here's the backstory. I have a '68 Dart with the 1970 ignition system; dual field squareback alt (Powermaster), electronic VR, dedicated 10g charge wire from the Alt Batt stud to the starter relay. Ammeter is hooked up and works, stock wiring through the bulkhead.
Over the 11 years I've owned the car, it's needed charging system maintenance/repair a few times. I replaced the brushes twice on the stock squareback before biting the money bullet and installing the PowerMaster. The VR has been replaced once, and that leads to my current dilemma.
System isn't charging again. Alt stud puts out 11.6V; the battery is 12.5V. Ammeter reads slight discharge. Key on-eng off, there's 12.4V to the blue Ign wire at the VR harness; harness plugged into the VR there's 11.7V on the blue wire at the alternator.
Engine running, I full fielded the alt and ammeter pegs to + charge (I turned off the engine before reading the volts on the MM). Pulled the VR harness, jumpered across the two harness terminals, disconnect and ground the blue Ign wire at the alternator; ammeter shows slight charge. So all signs point to a faulty VR.
Problem is, I bought a Mopar Performance VR 3438150 321 from Mancini Racing in July 2019. Only four years ago. I purposely bought a Mopar Performance VR because I didn't want to rely on a cheap O'Reilly's VR. And the final kick to the nuts is that VR cost $27.23 in 2019 (I have the receipt), today its $71 - $83 depending on Mancini, Summit, Ebay. Mancini sells a no-brand generic VR for $32.

So what are member's thoughts on today's VRs? Would you stay with the Mopar Performance or get a cheapo generic because they're going to crap out anyway? Look for a 50+ year old NOS? I assume the only difference between the 3438150 321, 419, and 271 are dating coding for restorations.
 
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Cruising Ebay, seller oldcarpartsnw has new OEM VR with the superseded part numbers 4111990 & 3874520 for under $30.
 
If not the above, then I don't know. Just about all of the so called brand names that I'm aware of have "gone china." Of course you cannot use a more modern one because they are inside the ECU. Other than that is the specialty aftermarket, a few of them have good reviews, but I have not tried them. And they are not cheap.
 
The only ones i find any good now days and all i use now are the Transpo HD Adjustable VR , i get them on Ebay for 22 bucks CND it says they are made in the US but for that price that is questionable .
 
The only ones i find any good now days and all i use now are the Transpo HD Adjustable VR , i get them on Ebay for 22 bucks CND it says they are made in the US but for that price that is questionable .
I did some research on them. Transpo has a manufacturing plant in Orlando, FL, which is also their headquarters.
Transpo was acquired by WAI in 2004, and operates as a wholly owned subsidiary. WAI is headquartered in PA but has a 100,000 sq ft facility in Shanghai, China.
Their narrative is impressive, but it's impossible to tell which products are built in the US or China.
How long have you had your Transpo VR? How does it adjust?
 
I Have been using them for a couple years with good success , they adjustment is a little screw on the back super easy i set my cars to 14v its easy on the wiring and enough to keep a full charge
I did some research on them. Transpo has a manufacturing plant in Orlando, FL, which is also their headquarters.
Transpo was acquired by WAI in 2004, and operates as a wholly owned subsidiary. WAI is headquartered in PA but has a 100,000 sq ft facility in Shanghai, China.
Their narrative is impressive, but it's impossible to tell which products are built in the US or China.
How long have you had your Transpo VR? How does it adjust?
 
Transpo HD Adjustable VR

How long have you had your Transpo VR? How does it adjust?
I agree that they work well. Easy to adjust but it is on the back of the unit. You have to hook a ground wire to the body of VR and car while making the adjustment.I have mine set at 14v.This is my first year with one after a 3 year battle with about 6 VR's that would over charge 15-16+ volts. Mopar Action did a article ,Rick Ehrenburg wrote about the Transpo VR with high regards.
 
It seems the field current is too high for the regulators.
If you can get a manfacturer to give you a spec on the current their regulator can tolerate, post it up.

The alternator's field current draw is pretty straight forward measurement, and many alternator's have that info available. Factory info is in the FSM.

Now as far as the ammeter readings go. If I read correctly its acting as if there is no wire around.
With the wire around, the ammeter should show discharge when running the car off of the battery. Same as no wire around.
But when the alternator is working, the ammeter should not show charge. At least that's what others have reported, and that makes sense. The shortest path, with least resistance, from the alternator to the battery should be the wire from the alt stud to the battery positive.

Regardless, wire around or not, recharge the battery if its real low from a charger.
 
Cruising Ebay, seller oldcarpartsnw has new OEM VR with the superseded part numbers 4111990 & 3874520 for under $30.

As I also have an over-charging problem (regularly 15-16V, sometimes up to 17V), I ordered one from oldcarpartsnw for less than $30.00 :
OEM NOS Chrysler electronic voltage regulator

I will report its performance as soon as I'll get it
 
Denso alternator swap complete
13 years without problems
img_3194-jpeg.jpg
 
As I also have an over-charging problem (regularly 15-16V, sometimes up to 17V), I ordered one from oldcarpartsnw for less than $30.00 :
OEM NOS Chrysler electronic voltage regulator

I will report its performance as soon as I'll get it
you must test the alternator's field current draw.
If it is supposed to be 3 amps, and its drawing 7 amps then its not fair to expect a voltage regulator designed for 3 amps to survive indefinately.
 
you must test the alternator's field current draw.
Instructions in the FSM.
It's the same as illustrated here for grounded field alternator.
Only difference with isolated field alternator is the need to ground one brush during the test.
 
I agree that they work well. Easy to adjust but it is on the back of the unit. You have to hook a ground wire to the body of VR and car while making the adjustment.I have mine set at 14v.This is my first year with one after a 3 year battle with about 6 VR's that would over charge 15-16+ volts. Mopar Action did a article ,Rick Ehrenburg wrote about the Transpo VR with high regards.
I've subscribed to MA for 12+ years; I'm going to look for that article.
 
I'm sure it's been a few years. Maybe 2-3 or more. Not much more because it is why I bought one.
It did sit in my parts stash so lets say 3 years ago.
 
I'm sure it's been a few years. Maybe 2-3 or more. Not much more because it is why I bought one.
It did sit in my parts stash so lets say 3 years ago.
I went online, but MA doesn't have a decent search function. I have all my old mags going back to 2012; gives me something to do tomorrow while cooking the brats. Thanks.
 
Instructions in the FSM.
It's the same as illustrated here for grounded field alternator.
Only difference with isolated field alternator is the need to ground one brush during the test.
The card attached to the PowerMaster alt only gives the output amps not the draw. I'm gonna call them and see what they have to say.
 
Currently using a parts store special with a later Denso alternator. But I have heard enough complaints that I am tooling up to start producing a line of USA-made, microprocessor controlled voltage regulators. Actually will be testing the first prototype today if all goes well.
 
1988 Toyota 4Runner (w/2.4 4-cyl) Denso. Use one on my 67 A100 and a 78 Magnum. I was able to simply tape up and tuck the VR wire connectors neatly away and pitch the VR, leave the bolt in the hole or use it to bolt down whatever else. If original appearance is not a concern then go Denso (plenty reman and new options) and never look back.:thumbsup:

1988 TOYOTA 4RUNNER 2.4L L4 Alternator / Generator | RockAuto

I’d remove the stamped cover on the back of these alternators and paint them black as the gray paint they typically are looks like dung.
 
Yesterday I installed the Transpo adjustable VR. OOTB it was charging 15.5V so I dialed back the pot a quarter turn counterclockwise and it settled on 14.46V at idle.
 
I found the article in MA. It's the April 2022 edition. The VR is referenced in the article titled Acid Test, about restoring a battery tray. As a subtopic, Ehrenberg goes into over-charging batteries causing the releasing of corrosive acid. He devoted a couple of pics to the adj VR, although he doesn't mention Transpo specifically. He did reference the eBay seller mcgworld_1; he's a Transpo dealer and the one that I bought mine from.
I'm glad I found the article because Ehrenberg believes 14.4V is too high, he set the VR to 13.9V. As previously mentioned I set the VR to 14.46V so I'm going go back it down some more.
 
set the VR to 13.9V.
I know I'm old school but we were taught that 13.8 was the correct voltage.
What I remember the instructor saying that to charge a battery a higher voltage than 12.6
is necessary to push the voltage into the battery and at 13.2 to a maximum of 14.
14 as the highest as not to boil the electrolyte .That was 50+ years ago. So are our cars.
 
I know I'm old school but we were taught that 13.8 was the correct voltage.
What I remember the instructor saying that to charge a battery a higher voltage than 12.6
is necessary to push the voltage into the battery and at 13.2 to a maximum of 14.
14 as the highest as not to boil the electrolyte .That was 50+ years ago. So are our cars.
That's almost exactly where Ehrenberg stated. I'm shooting for between 13.8-13.9.
 
I have been using the 90 amp Denso alternator and transpo regulator for many many years. Set the regulator for 13.8-13.9 volts. Never had any issues/failures. Even my race car, and I use a micro switch on the throttle to open the field circuit at WOT. Several of my cars are the 64-66 "A" bodies with the alt/reg the late style
 
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