High Output Alternator Help

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MadMaxCustoms

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Hello,

I have a 1972 factory 318 AC Dart Swinger 2 door. It has an old alternator in it and my light are real dim at idle. Does anyone know of a high output alternator that I can install? It needs to have the ability to run 2 belts on it. One to the crank obviously and the other one goes to the AC compressor. Or is it possible to take the pully off the one I have and put it on another one.

Thanks!
 
Hello,

I have a 1972 factory 318 AC Dart Swinger 2 door. It has an old alternator in it and my light are real dim at idle. Does anyone know of a high output alternator that I can install? It needs to have the ability to run 2 belts on it. One to the crank obviously and the other one goes to the AC compressor. Or is it possible to take the pully off the one I have and put it on another one.

Thanks!
Most alternators come in 1 and 2 groove options.. also you can rent a tool at the parts store to take the pulley off but it usually doesn't leave it in that good a condition....
 
sure it's just the alternator? you should make sure all the electrical connections are good or your just going to have the same problem
 
It's pretty normal for Chrysler charging systems on these old cars to operate like that. How is it at say 1500 RPM?
 
Let's manage by fact.

When idleing what is the voltage at the headlight connector?

Also some rebuilt alternators have a pulley that is larger diameter than stock.

Also you may be used to newer cars with bright headlights.
 
It's pretty normal for Chrysler charging systems on these old cars to operate like that. How is it at say 1500 RPM?

Yes I am aware that it may be normal but I dont want it on this particular car. Lights brighten with acceleration. My radio shuts off when the car is at idle at a stop light. Shakin my damn head...
 
. My radio shuts off when the car is at idle at a stop light. Shakin my damn head
You have major electrical issues if that is happening.

You need to do as others have said and readup on the typical issues.

If you don't correct the issues you could have a fire in your electrical system.
 
Yes I am aware that it may be normal but I dont want it on this particular car. Lights brighten with acceleration. My radio shuts off when the car is at idle at a stop light. Shakin my damn head...

Yeah, no ****. I know you don't want it like that. I asked what it did at a specific RPM for a reason, not just blowin it outta my ***.
 
Yes I am aware that it may be normal but I dont want it on this particular car. Lights brighten with acceleration. My radio shuts off when the car is at idle at a stop light. Shakin my damn head...


What RPM are you idling at???

My local alternator rebuilder cautioned me that as you bump up the output (amps) of the alternator, the less it generates at low RPM...

also putting the trans in neutral while idling at a light will allow it to idle higher and the alternator will put out a little more...
 
If you are staying with Mopar alternators, you need to first, use the "squareback" design rather than "roundback." Also it's not just simply rated output. One of the lower output (I think 47A) has higher LOW RPM output than some of the higher output AKA 55-60A units.

Make certain the belt is not slipping, that the pulleys are not glazed, and THAT THE PULLEYS are proper sized, IE that some "drag racer" has not installed a larger alternator pulley to slow it down

Another thing you can do is get it idling with "everything on" and measure voltage at the battery + with one lead of your meter, and at the alternator output stud with the remaining probe of your meter. This should give a quite low reading and WILL BE THE VOLTAGE DROP of the charging path/ wire from the alternator to the battery.

These girls are well known for voltage drop problems in the bulkhead connector/ ammeter circuit and drop in that line WILL cause additional sag at low RPM

If you insist on "really great" low RPM voltage, you are going to likely have to convert to something like a modern Denso or one off a Dakota/ RAM, etc
 
If you are staying with Mopar alternators, you need to first, use the "squareback" design rather than "roundback." Also it's not just simply rated output. One of the lower output (I think 47A) has higher LOW RPM output than some of the higher output AKA 55-60A units.

Make certain the belt is not slipping, that the pulleys are not glazed, and THAT THE PULLEYS are proper sized, IE that some "drag racer" has not installed a larger alternator pulley to slow it down

Another thing you can do is get it idling with "everything on" and measure voltage at the battery + with one lead of your meter, and at the alternator output stud with the remaining probe of your meter. This should give a quite low reading and WILL BE THE VOLTAGE DROP of the charging path/ wire from the alternator to the battery.

These girls are well known for voltage drop problems in the bulkhead connector/ ammeter circuit and drop in that line WILL cause additional sag at low RPM

If you insist on "really great" low RPM voltage, you are going to likely have to convert to something like a modern Denso or one off a Dakota/ RAM, etc
FYI I just installed a Power Master 100 amp one wire in my car in gear at 800 rpm charge voltage is 14.1 VDC
 
Most alternators come in 1 and 2 groove options.. also you can rent a tool at the parts store to take the pulley off but it usually doesn't leave it in that good a condition....
With the proper tool the orginal pulleys come off without any damage.
Reinstalling the pulley is not difficult but requires removing the end shield and using a press.

Two types of pullers shown post 11 & 8
upload_2019-3-20_21-40-24-png.png


upload_2019-3-20_8-28-55-png.png


upload_2019-3-20_8-48-9-png.png



Another type made by Dave in post 10
upload_2019-3-20_10-2-25-png.png


Snap-on version posts 12 and 14
944e6372-960d-4eff-b554-5c74fea56f66-jpeg.jpg


Installation without a pressure gage on the press discussed in post 2
Alternator repair, a little show and tell.
 
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With the proper tool the orginal pulleys come off without any damage.
Reinstalling the pulley is not difficult but requires removing the end shield and using a press.

Two types of pullers shown post 11 & 8
View attachment 1715615555

View attachment 1715615556

View attachment 1715615557

View attachment 1715615558

Another type made by Dave in post 10
View attachment 1715615559

Snap-on version posts 12 and 14
View attachment 1715615560

Installation without a pressure gage on the press discussed in post 2
Alternator repair, a little show and tell.
I used those tools on mine and still it boogered the pulley... Was no big deal as I was putting a billet pulley on. But I'm sure I still have it out there in the garage...
One turn deserves another I disagreed with your post because even with the best tools sometimes it doesn't come out right.. that's been my experience...
 
I used those tools on mine and still it boogered the pulley... Was no big deal as I was putting a billet pulley on. But I'm sure I still have it out there in the garage...
One turn deserves another I disagreed with your post because even with the best tools sometimes it doesn't come out right.. that's been my experience...

If it was one of those waiwei pulleys, IMO they belong in the trash. The ones I've had have tighter bore diameter than factory amongst the other dimensional issues. Good for paperweights and recycling.

We'll have to run a poll. So far its 3 out of 4 of us have had no problems removing, at least with factory pulleys.
 
If it was one of those waiwei pulleys, IMO they belong in the trash. The ones I've had have tighter bore diameter than factory amongst the other dimensional issues. Good for paperweights and recycling.

We'll have to run a poll. So far its 3 out of 4 of us have had no problems removing, at least with factory pulleys.
Okay so this is the deal LOL I had a cheap Chinese remanufactured alternator. I bought the cfv billet pulley. I went down to AutoZone and rented their puller. I used it correctly. give me enough credit for knowing what the hell I'm doing.. it kind of distorted it as it pulled it off.. I can go to the garage look for it and take a picture of it if you don't believe me but I would rather sit here in my chair and finish my coffee... I had to completely pull the alternator apart to press the new one on which one on nicely.
But really answered that op's question Beyond Summit any parts store should have a 1 and 2 groove alternator pretty much in any desired output.. if like everybody's saying that's even problem...
Personally I've had more issues with regulators than anything...
 
Hello,

I have a 1972 factory 318 AC Dart Swinger 2 door. It has an old alternator in it and my light are real dim at idle. Does anyone know of a high output alternator that I can install? It needs to have the ability to run 2 belts on it. One to the crank obviously and the other one goes to the AC compressor. Or is it possible to take the pully off the one I have and put it on another one.

Thanks!

Tuff stuff makes a 100 and a 130 amp 1 wire unit in a Chrysler case and It can be had with single or double pulley
 
Most auto stores will swap the pulley for you and befor you go and throw a 100amp alternator at it you need to update/upgrade/bypass the factory wiring. Below explains how Ma Mopar did it.

Catalog

Might upgrade your headlight harness.
[FOR SALE] - Plug and play - Headlight Relay Kits

and get better headlights
Hella Vision Plus Conversion Headlights 002395301

if you want LED headlights look to JW Speaker
J.W. Speaker - Engineered Lighting Solutions


I want a set of those JW 8700 series headlights in the worst way
 
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