Alternator upgrade ??s

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tooslow

tooslow

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I have a BB 512 with MSD ,elec fuel pump, Fans , ect... Running the stock 65 amp with external regulator
Is there a simple Alt upgrade to 125 amps and LOW RPM CHARGING (my issue)
I see POWERBASTARDS has a 140 amp for 350 dollars . Can a stock external regulator handle 140 amps ?
Is a One Wire a good option ?
 
You won't be getting "140 amps" output very often. If the system is only using 40amps that's all you'll get no matter what the alternator you use is rated for. What about a factory 100a from 70s/80s?
The last couple of years of police diplomat they used a either a 90 or a 120 amp alt with that same regulator as the 65 amp unit took
 
volaredon said:
You won't be getting "140 amps" output very often. If the system is only using 40amps that's all you'll get no matter what the alternator you use is rated for. What about a factory 100a from 70s/80s?
The last couple of years of police diplomat they used a either a 90 or a 120 amp alt with that same regulator as the 65 amp unit took
Click to expand...
thank you
 
I'd add up the amp draw of all of your circuits to help determine the output you'll need out of an alternator.

I'm a fan of the denso style alternators. Mancini sells some pretty trick mounting bracket kits for them too. Here's to 90 amp unit on my '66.

1691426655068.png
 
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Go Denso as mentioned above. Believe all the members on this site who have done the upgrade and posted their results. You won’t regret it.
 
I like the Denso but also a bracket is needed .
My total draw at idle is 115 amps .
I checked with Powermaster, AWESOME customer service !!
Make a one wire drop in for $280 that puts out 120 Amps at 1000 RPM .
The tech said One wire conversion consists of a 4 gauge to the starter and a 4 gauge to the engine block. Then remove the external cowl mounted factory regulator . Available at Summit #48529-104
I had read that one wire alternators do not produce at idle but Powermaster told this is true of the Chinese Junk one wire alternators. Powermaster is a different design
Any thoughts on the Powermaster One Wire Alternators ?
 
tooslow said:
I have a BB 512 with MSD ,elec fuel pump, Fans , ect... Running the stock 65 amp with external regulator
Is there a simple Alt upgrade to 125 amps and LOW RPM CHARGING (my issue)
I see POWERBASTARDS has a 140 amp for 350 dollars . Can a stock external regulator handle 140 amps ?
Is a One Wire a good option ?
Click to expand...
For what it's worth, I just upgraded to the black version of this one and I absolutely love it. Chrysler 1 Wire Alternator, 100 Amp, Chrome Plated V-Belt Pulley

CVF warranties thier accessories for life. Have had awesome luck with them, and I own 2 of thier systems.

I had a "140 amp" Tuff stuff that never charged at idle, even after sending back years ago to exchange/rework. It was a 1 wire. Full disclosure I did have it probably 8 years, but it never charged at idle, and recently burned up its internal regulator and took my battery with it.

The cvf is only marketed as a 100 amp, however i can tell you with an a2000 fuel pump, elec water pump, and 2 big SPAL fans all on, this baby will idle at 900, and still put out 13v+. I would buy it again in a heartbeat.
 
If idle charging is the issue then change the alternator pully to be smaller diameter.

Many of the repo have a 3" pulley when a 2.5" is what the stock pulley was.

Disclaimer....

Your crank and alternator pulley diameters need to be matched so the alternator is spinning the correct rpm at a given engine rpm

With a 6 to 6.5 crank and a 3 alt, it's too slow. But with a 2.5 it's fine.
 
Demonic said:
I wonder if they're made in two v belt?
Click to expand...
They may, I know they make it in a serpentine also. Would just have to call and ask them. I run thier crank pulley also. They do seem to have plenty of options.
 
There are variations of the basic alt design that result in different charging characteristics. Look for an alt that outputs high amps at low rpms.
You should also find out the max shaft speed of the alt. Changing pulley ratios, max engine rpm could exceed the safe shaft speed.
 
Your draw at idle is 115 Amps?!? Don't forget to seriously upsize the conductors. To keep voltage drop reasonable, you'll want a 4 or better yet 2 AWG wire from the alternator to the battery (or wherever your loads are bussed).
 
Dana67Dart said:
If idle charging is the issue then change the alternator pully to be smaller diameter.

Many of the repo have a 3" pulley when a 2.5" is what the stock pulley was.

Disclaimer....

Your crank and alternator pulley diameters need to be matched so the alternator is spinning the correct rpm at a given engine rpm

With a 6 to 6.5 crank and a 3 alt, it's too slow. But with a 2.5 it's fine.
Click to expand...
i tried 3 different pulley diameters with my Tuff stuff, it was just a dud.
 
Using an OE late '80s 100 amp 318 alternator myself; I believe it's one of the Denso family. Theoretically you can use a points-type regulator with it. Mine died about when I installed this alternator and I converted to a solid state type.
 
The MADD wiring information is very helpful. The stock wiring has issues with corrosion and increased resistance at the bulkhead connector, so don't run high amperage through it.

Also, remember that upsizing the grounds from the alternator to the block, chassis and battery to the same size as the positive cables you run allows the charging circuit to flow equally through positive and negative circuits.

I run a rewound CS 144 with a heavy duty bridge rectifier and basically the MADD wiring.

IMG_2602.JPG
 
jbc426 said:
The MADD wiring information is very helpful. The stock wiring has issues with corrosion and increased resistance at the bulkhead connector, so don't run high amperage through it.

Also, remember that upsizing the grounds from the alternator to the block, chassis and battery to the same size as the positive cables you run allows the charging circuit to flow equally through positive and negative circuits.

I run a rewound CS 144 with a heavy duty bridge rectifier and basically the MADD wiring.

View attachment 1716126080
Click to expand...
I agree. Read MADD info. Original bulkhead connector contacts were not designed to carry high currents, even when clean. Original equipment alternators were rated at 35A.
 
My go to up grade has been A 1989 D350 with the Magnum 5.9 had an optional 120A Denso setup for two V belts. Almost bolt in (spacers for alignment) and terminal changes on the field wires.

IMG_0038.jpeg
 
tooslow said:
I have a BB 512 with MSD ,elec fuel pump, Fans , ect... Running the stock 65 amp with external regulator
Is there a simple Alt upgrade to 125 amps and LOW RPM CHARGING (my issue)
I see POWERBASTARDS has a 140 amp for 350 dollars . Can a stock external regulator handle 140 amps ?
Is a One Wire a good option ?
Click to expand...
Well, just changing to a higher output alternator is not the end of the job. Are you using the stock ammeter? The a.meter shunt needs to be capable of the current you will.put through it. Take the original 60 amp off and install a 100 amp and if you draw the 100 amps, the shunt could get hot and cause a failure or fire.
I worked on an ambulance once and installed a 100A alternator to power extra equipement they had installed. Melted the ammeter. The wiring to and from the ammeter where charging current will flow also needs to be up to the job.
In normal operation the alternator should only output the sum of all the draw of the end devices. Temporary items such as power windows or locks are surge power and not generally a problem. Lights, AC or a high power sound system create that long time draw that builds heat. That was the problem for the ambulance, a new baby incubator and 3 hour transfer times from the small town.
Sometimes best to connect the two ammeter wires, remove the ammeter and install a volt meter.
 
Dale Davies said:
Well, just changing to a higher output alternator is not the end of the job. Are you using the stock ammeter? The a.meter shunt needs to be capable of the current you will.put through it. Take the original 60 amp off and install a 100 amp and if you draw the 100 amps, the shunt could get hot and cause a failure or fire.
I worked on an ambulance once and installed a 100A alternator to power extra equipement they had installed. Melted the ammeter. The wiring to and from the ammeter where charging current will flow also needs to be up to the job.
In normal operation the alternator should only output the sum of all the draw of the end devices. Temporary items such as power windows or locks are surge power and not generally a problem. Lights, AC or a high power sound system create that long time draw that builds heat. That was the problem for the ambulance, a new baby incubator and 3 hour transfer times from the small town.
Sometimes best to connect the two ammeter wires, remove the ammeter and install a volt meter.
Click to expand...
The probalem with all of this stuff is trying to run all that electric (whether its the ambulance extras or the EFI extras) on a wiring strategy designed around totally different requirements. All the standard system needed to do was (a) start the engine (b) allow the alternator to run a few items and recharge the battery. The highest loads were battery and that was just for very few minutes, and then lights and 'accessories' like wipers and heater blower.

That's pretty much out the window with the OP's car. It needs a bunch of electric power at all times just to run the engine. During start the battery draw down will be higher than factory, meaning the recharge will be higher given power at the same voltage.

I'd suggest redesigning the system. You don't have to toss all the original - some subcircuits may be fine. Focus first on the main feed or feeds. Whether you want to use the battery as a filter depends on your electronics. Not a concern on the origina l system but may be with your stuff.

Discussion here about a Chrysler RV with two batteries but not quite the same issues as running loads are very basic other than the RV battery recharge needs.
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Ammeter to Voltmeter...who does it?

My bulkhead connector is gone. I'm wiring a painless harness in. 10 g wire from the alternator to the ign switch side of a 70 amp maxi fuse. What size cap did you use? soldered across pin 1 and 2? Pin 3 is 5V out?
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if battery is not needed in between the alternator and the electronics, then a strategy like this can be used (with or without an ammeter). if using an ammeter consider a shunted unit or one made for the recharge/discharge loads expected.
1691952926683.png


or have a second fuse/relay box in the engine compartment
1691953009108.png

The alternator output wire in the diagram above still needs a maxi fuse or fusible link between it and the battery in case the alternator shorts.
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Fusible link or not?

I am going to install a relay to power a fused distribution block to power things like the line-lock, the efi, distributor, ignition box. Since I can put appropriate fuses for each item, would be beneficial or detrimental to put a fusible link in the line to power the relay. If so, would you...
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