Alternator connection and pulley question.

Daniel Romero

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The cheap Duralast alternator I got a few years ago is crapping out. I’m going to upgrade to a 90-95 amp one this time. I’m considering going with a PowerMaster or a Remy.
I have a few questions:
1.) Is Remy a reliable manufacturer?
2.) PM alternators offer theirs “externally regulated” or as a one-plug option, and i believe different options as far as where the connection is located. Which do I need? I’ll attach the pictures of my options below.
3. I know I need an alternator with the two-groove pulley, but it looks like there are different widths of the grooves to choose from. Which do I need?

This is for my 1973 Plymouth Fury III with a 400. It’s all original as far as wiring.
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If you car has A/C, it will have a 2 groove pulley, otherwise they are single groove pulleys for most stock applications. Unless you plan to install cooling fans in place of the factory steel fan or a 6000 watt stereo blaster, you do not really need a 90 amp alternator. If you want to go that route, you will need to upgrade the charging circuit wiring to handle the additional amperage. You have a car with 50+ year old wiring and that is an accident waiting to happen if you throw 90 amps at it. There are several posts on this website about the high amperage upgrade, read those a decide how you want to proceed.
If your car is a '69 or older model, it came with a round back alternator with an external mechanical regulator and it will have the one wire field connection. '70 and later usually had an externally mounted electronic regulator with a two wire field connector. If you plan to eventually convert to electronic ignition, then you will need an electronic voltage regulator so that you do not fry the electronic ignition. If you plan to stay with a point style ignition, the conversion to an electronic regulator is not needed but it can be a desirable upgrade as the electronic regulator provides a more steady rate of charge at low RPMs. There are several posts on this site on how to do the electronic regulator conversion. A lot of this depends on how close to stock you are planning to keep this car.

A lot of today's rebuilds are poor quality where the rebuild consists of replacing only the part that failed. A lot of these low end rebuilds, think Duralast, are also done overseas where the replacement parts are of highly suspect quality, think the finest chineseium. You get what you pay for. go to a supplier of quality US sourced rebuilds.

Dave
 
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If you car has A/C, it will have a 2 groove pulley, otherwise they are single groove pulleys for most stock applications. Unless you plan to install cooling fans in place of the factory steel fan or a 6000 watt stereo blaster, you do not really need a 90 amp alternator. If you want to go that route, you will need to upgrade the charging circuit wiring to handle the additional amperage. You have a car with 50+ year old wiring and that is an accident waiting to happen if you throw 90 amps at it. There are several posts on this website about the high amperage upgrade, read those a decide how you want to proceed.
If your car is a '69 or older model, it came with a round back alternator with an external mechanical regulator and it will have the two wire field connections. '70 and later usually had an externally mounted electronic regulator with a single wire field connector. If you plan to eventually convert to electronic ignition, then you will need an electronic voltage regulator so that you do not fry the electronic ignition. If you plan to stay with a point style ignition, the conversion to an electronic regulator is not needed but it can be a desirable upgrade as the electronic regulator provides a more steady rate of charge at low RPMs. There are several posts on this site on how to do the electronic regulator conversion. A lot of this depends on how close to stock you are planning to keep this car.

A lot of today's rebuilds are poor quality where the rebuild consists of replacing only the part that failed. A lot of these low end rebuilds, think Duralast, are also done overseas where the replacement parts are of highly suspect quality, think the finest chineseium. You get what you pay for. go to a supplier of quality US sourced rebuilds.

Dave
I hate to sound like I am trashing you Dave, but 1969 and older are the single wire, and 1970 and newer are the dual wire.
Happy Holidays.
Bill
 
I hate to sound like I am trashing you Dave, but 1969 and older are the single wire, and 1970 and newer are the dual wire.
Happy Holidays.
Bill
I do not consider correcting mistakes to be trashing. Edited the post to correct it and thanks for noting I had it *** backwards. Old brain.

Dave
 
Be careful with the terminology. In the ads posted above, "1-wire" does not mean that it has a single field wire, but that it has been converted to an internal regulator like a GM 1-wire alternator. That is not what you want.
 
I installed a Remy remanufactured unit from Rock Auto, works great. They split off from Delco-Remy a while ago.
Also have a Remy starter, works great as well, but my only complaint is it doesn't have the classic Mopar starter sound.
 
I installed a square back in mine and upgraded the wiring bought my alternator at Napa stay away from powermaster when it takes a crap and you'll be waiting for shipping to get you up and going again
 
I have never used the Remy brand so not sure about the quality. Powermaster has a decent reputation. I like Dave's suggestion about upgrading the wiring for the charging circuit. I do like a high amp output alternator if you really need it, electric fans, EFI, electric fuel pump, stereo system, you get the picture. A stock coil and nothing else operating (daytime driving without lights) doesn't need it.
 
I use Duralast at present because VatoZone honors their warranty without fuss. This is my 3rd 60 amp dual groove pulley roundback in almost 4 yrs too, so as Dave says, you get what you pay for with this sino-sludge stuff.

I upgraded my charging circuit wiring within a month of buying Mathilda because due to a broken motor mount allowing the alternator charging stud to short out, I had a wiring fire one night. No big deal to me, but most folks would flip out over that sort of ****. I took it all as a matter of course, being happy to drive the car home for little $$.

Anyway, I ran #8 stranded wire to the charging stud right away, and still use it. I purchased a mid 1970s charging stud connector, also #8 AWG, soldered and shrink-wrapped it to the #8 I had run earlier, and am happy with that. I replaced the original, burned wires going to the starter relay in #8 for the relay and dash circuits, and #12 for the voltage regulator. All this is at least 2 sizes larger than what came in the original harness, and I've had no further trouble with this. I also replaced what goes from the bulkhead connector in #12, punching out the old blade connector and running it straight through. For crucial wiring, the fewer connections, the better.

I've put the headlights on 30 amp Tyco-Bosch relays, engaged by the original drivers-side low-beam connector, and separately powered straight from the battery with fused link protection to the line side of the relays, and 30 amp breakers which pop into the 1.25 inch x .25 inch glass fuse holder which originally had 30 amp fuses in it. On the minuscule chance that a short from the loads (headlights) could occur, I decided a breaker would be a bit safer, though I've lost headlights while rolling at night before sans difficulty, but I have extraordinary night eyes.

I wired this harness in #10 AWG, to allow plenty easy current flow.

Apropos of that crucial concept, if you want a 90 amp alternator, I advise you to use at least #4 AWG stranded wire from your alternator post. Use #8 AWG fusible link wire to connect to the alternator post. You could go with #2 AWG for the main charging conductor, and two identical lengths of #10 AWG fusible link wire in parallel to make the proper link for something that heavy, OR install a 100 amp fuse or breaker to protect your charging circuit. I figure for 90 amps, #4 should carry it with the #8 link wire, BUT, if you like to oversize your conductors as I do, you can bump them up a size for peace of mind.

I like the Tuff Stuff line I've seen, but haven't tried this brand so can't tell you anything on any personal empirical basis. I CAN tell you that I've had no major trouble with my charging system since I rewired it, other than the sorry quality of Duralast products. Be that as it may, the local Blottozone staff all know me and happily replace their widgets when I appear with one in hand and scowl on face.....
 
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