140 amp Alt

[Jacksboys]

I know that there have been bad experiences with Powermaster, but I was wondering has anyone ever tried the GM single wire 140 amp powermaster version? 

My father is going to use this on his Dart, just wanted to see if anyone had any experience.

[MEK-Dangerfield]

I have no experience, but he will definitely have to beef up the wiring to pull this off.



  Mike

[Jacksboys]

I have no experience, but he will definitely have to beef up the wiring to pull this off.



  Mike

He is just running a single wire to the battery and bypassing the external regulator because it has an internal one.

[MEK-Dangerfield]

He is just running a single wire to the battery and bypassing the external regulator because it has an internal one.

I understand that, but this alternator is twice the output of what the stock alternator would be supplying. He would need to use a much smaller gauge wire in this case.


  Mike

[Bullitt-]

I understand that, but this alternator is twice the output of what the stock alternator would be supplying. He would need to use a much smaller gauge wire in this case.


  Mike

Mike I think you mean larger gauge which has a smaller numerical I.D.

[MEK-Dangerfield]

Mike I think you mean larger gauge which has a smaller numerical I.D.

Yep. 

  Kind of like the gears in the rear end. Bigger gears, mean smaller number ratio. Go figure. 


  Mike

[Jacksboys]

I understand that, but this alternator is twice the output of what the stock alternator would be supplying. He would need to use a much smaller gauge wire in this case.
  Mike

I miss understood you.  Yes the wire that goes from the Alt to the battery is (I think) #2 gauge.

[Moparal]

Just wondering why your dad wants such a big amp alternator. If he is racing the car, he will need a shut off switch. The drag is quite a bit. Does he have big stereo stuff and a/c? I haven't ran across a reason to go bigger the 70 amps on my e bodies. I usually stay around 50 amps. But I don't have big stereos in my cars either. I never run out of amps for what I need.

Is this a want need or does it have a purpose?
Just curious
Ahhh High speed in the lobby of this motel

[Jacksboys]

He was always irritated when ever the car would idle the lights would go dim, the wipers would almost quit, and the a/c-heater blower would almost stop.  A few years ago, this was his daily driver, and now that he is retired, he plans to make it his main tranportation again.  He does not really need the total amperage, but the few times he got to test drive the car, he was very happy with the outcome of the Alt.

[ROMI]

I've been wondering if that is really the reason the lights dim.
I hate that and I'd like to fix it but I really haven't read anywhere that a higher amp alt is the solution.  Someone else on this site said to clean all the connections.  So what's the fix?  A 70 amp alternator?

[Bullitt-]

I've been wondering if that is really the reason the lights dim.
I hate that and I'd like to fix it but I really haven't read anywhere that a higher amp alt is the solution.  Someone else on this site said to clean all the connections.  So what's the fix?  A 70 amp alternator?

In my case the headlights & instrument lights would dim/pulse at idle, Polishing/cleaning contacts/wiring connections solved the problem but I guess a weak alternator would give similar issues. 

[Oldschool]

On some of my old hot rod Mopars back in the day, we had a simple fix for that:  Install a smaller pulley on the alternator and it makes it spin faster.  Faster spinning = more output and the lights didn't dim, and the battery stayed charged all the time.  Only beware and don't go too small, or you can sling the alternator apart at high rpm's.  (Don't ask how I know that).  I used a small pulley and got an alternator with a 1 year warranty.  After a few months, I would sling it apart and go get another one free.  Worked out ok for me......               

[MEK-Dangerfield]

Make sure your voltage regulator has a good clean connection to the body(ground). That is what tells the alternator to put more juice to the goose. I don't have this problem, even with a beefy amp on my stereo. My alt. does put out 80 amps though.


  Mike

[duodec]

My understanding is that the early Chrysler alternators produced very low output at lower RPMs, so when you are idling with lights and other accessories on, the alternator output is less than the power being drawn, so the system draws down to battery voltage (12v instead of the 13v+ from the alternator) and pulls power from the battery to make up the shortfall.  Oldschool's post about using a smaller alternator pulley was one workaround.  I've also read that some rewound rotors and stators were once available that could provide more output at low RPM (at the cost of higher drag) but I was never able to find such a set.  They are NOT the same as the "high output" rebuild parts sold in some catalogs.

The high output Mopar alternators (and rebuild kits) sold by aftermarket places used to have a bad rep for the same problem; you'd get the 70-120 amps at high RPM, but low RPM output could be even worse than the stock units.

One of the magazines back then recommended using alternators from late '70s-'80s cars that were identifiable by the very thin stator ring; earlier alternators had that 1/2-ish inch stator ring visible between the case halves; the later ones had a much narrower ring.  Those late alternators still look reasonably correct (compared to a GM unit) but reputedly had much better low RPM efficiency than the early ones.

Sadly they also mentioned that the GM 1-wire units were still better...