Stock Alternator Actual Amp Ratings/Specifications?

[1984GTTurboVert]

Is there anywhere i can find the rated and actual charging specifications for the factory oem motorcraft 1g alternators?
More specifically has anyone ever tested them and got the actual numbers from them under use?

[KevinK]

The amp rating is usually stamped on the front housing. I have heard rebuilders would rebuild to all one level upgraded amperage like 65 amps. There used to be kits to increase the output to 100 amps. I think have one in one of my 60s cars and another kit on the shelf.

[1984GTTurboVert]

I know about the case having a stamp, but what were they actually putting out is what im interested in. I mean wear and time not withstanding.

Case in point, my 83 tbird has a 65 amp alternator because of options. Ok, so does it really put out 65 amps, and is that at idle, cruising or top output?
My mustang has a 60 or 65 amp alternator, has anyone bothered to verify they were getting that out of it or has the motorcraft 1g ever been tested to verify their output.
People jump right to the 3g upgrades but how much are they "really" getting over stock 1g actual output?

[KevinK]

1 G does not put out full power at idle, at least that's the rumor. I believe you need to manually switch it on to get full power.

[85GTGuy]

Ok, so does it really put out 65 amps, and is that at idle, cruising or top output?

An alternator's listed output is at some elevated rpm.... not at an idle. And, I think, then only if the electrical system needs it.

[1984GTTurboVert]

Every time i ask people they tell me its the max "continuous" output they rate them with. Honestly, i always thought that also.
I was going to test both of my cars output but the thing i was going to use(old sears timing thingy) it wouldnt budge at all on the amps setting. Maybe i wasnt using it right no instructions with it.
The multimeter i have wont do amps so ill pick up one that will and answer my own question with their outputs.

[1984GTTurboVert]

Just wanted to update this, i was busy working on other stuff but tried to run a quick test since i had stuff to do it handy.
I tested the factory one on my mustang and the aftermarket 100 amp one i picked up to replace it.
I used a kal equip engine systems analyzer to test it, old tool but i think ford had a rotunda version of this tool for this.
Nothing was on during the test but what is needed to run the car.
My battery was at 12.4 v before starting the car.
The factory 60 amp one put out 39 amps at 1800rpm.
The aftermarket 100 amp one put out 58 amps at 1800 rpm.

[82GTforME]

I bought a reman one on RockAuto in a pinch for my SVO a couple of years ago. It had a test report in the box. I never really looked closely at it or thought to but still have it and no issues with it but I do not test it's capabilities when I have it on the road.

[KevinK]

Did you put maximum load on it?

Head lights on high beam, ac blower on max, radiator fan on, ac compressor running, rear defrost on, wipers on.

I would not expect max output on the 1 G at 1800 rpm's. Try 3000 rpm's.

[1984GTTurboVert]

Did you put maximum load on it?

Head lights on high beam, ac blower on max, radiator fan on, ac compressor running, rear defrost on, wipers on.

I would not expect max output on the 1 G at 1800 rpm's. Try 3000 rpm's.

No, i put the minimal load possible on it. The tool said to do it at 1800 rpms but wasnt specific about motor rpms or alternator rpms. It was at motor rpms. I didnt even jumper the regulator.
Im going to do this test again when my new multimeter comes since its got an amp clamp that reads dc amps up to 100. The thing i used had a shunt but it wasnt a very good connection(because of space and wire length) so im in doubt about the readings. It was a quick test ill do a proper one when i can.

[83GTTops]

I bought this 'Powermaster 7078' '75 Amp' Alternator after being disappointed with the one from 'Advanced Auto'. I really like it.

It had the wrong pulley on it, but that was not a hard change.



https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

[1984GTTurboVert]

I bought this 'Powermaster 7078' '75 Amp' Alternator after being disappointed with the one from 'Advanced Auto'. I really like it.

It had the wrong pulley on it, but that was not a hard change.



https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

I bought one(7078 75amp) awhile ago but havent decided if i want to use it in my other fox car. Ill keep it in case i decide to go down that road.
Its nice and comes well packaged, they come with a test result slip but its not specific to what rpm it was tested at.