alternator conversion

[dkn1997]

with the addition of fuel injection (electric pump), extra electric fan, and a planned addition of aftermarket a/c, I want to upgrade my stock alternator in the charger (40 amp?) whatever, I feel I am pushing it already, especially at night with lights, fuelpump, etc.

I really do not want to spend 200 bucks for a powermaster. I heard that you can use a late 70's alternator in my car if you change the regulator and add a field wire. the 78 amp would be an improvement, and I think there are higher amp ones available.

Has anyone done this swap? exactly what alt would fit (part #, year of donor car)? how about that wiring, anyone know exactly what to run and where to run it?

I am thinking that once I have part #'s etc...., I will go to the local parts store and grab the stuff. Or is there another way I should be going.

Currently, no starting problems. But, and there is always a but, at idle with brake on, Idle is a bit jumpy, tach dips down from @900 to 700. Take foot off brake, and idles smooth. (manual brakes) jumps with headlights or electric fan on, too.

I realize that alt may not be causing this, but I want to change it anyway to make room for future upgrades

As usual, any advice woudl be greatly appreciated.

Kevin

[Doug Wilson]

The last time I did an alternater upgrade, I just went down to the parts store and asked them what I should get. They set me up for about $40, and it's been working for about 10 years.

[dkn1997]

doug, could you be more specific? curious as to what you upgraded from and what you ended up with-

[ehostler]

If you want a great setup, currently there is a near new 130 AMP ND Alternator on ebay (from an '02 Dodge conversion van). They are asking $74 + $14.95 shipping. Then ad the '70s regulator and wire it all up.

If done correctly, you will never have a low current problem again.

[dkn1997]

I checked out that ebay alt, I do not know if it will fit, and also that whole serp belt deal, do not know if I could change that to reg pulley setup, good price, though

[John Kunkel]

Wiring the newer alternator/regulator:

http://www.imperialclub.com/Repair/E...l/charging.htm

[polarapete]

I did the late alternator upgrade to my '64. I went from a single field to a dual field with the late electronic VR. Most of the changes were outlined in various articles in the Mopar Action magazine.

I felt I needed the improvement because of the Electric Cooling Fan, Electric Driver's Seat etc.. So far, so good.

Check www.moparaction.com

[dkn1997]

thanks, john, I checked out that page and looks simple enough, now to just get the right parts-

I think that the connector on the reg is going to be tough to find. boneyards here are picked clean, not much luck with anything more than 15 yrs old!

[ehostler]

Originally posted by dkn1997@aol.com
I checked out that ebay alt, I do not know if it will fit, and also that whole serp belt deal, do not know if I could change that to reg pulley setup, good price, though

The pulley can be changed. Either a '70s style MOPAR or GM pulley will work fine. The unit will fit, however, you will need to go to the hardware store and get a $3.00 bushing/spacer, to make it fit.

If I were employed right now, I would buy one of those alternators for my '69 Coronet.

As far as the regulator connector goes, if you can't get it anywhere else, I'm sure that Texas Acres can get you one.

[George G. Leverette]

Some one suggested getting an alternator for a 1985 Dodge
D-150 truck for better output at lower RPM. I followed this suggestion because the dist on the car had stripped threads. The alternator was an exact duplicate with one exception "The pulleys on the truck alternator were smaller in diameter". The alternator will hold at the 12 oclock position even with lights and accessories on.

[rebby]

i went w/a high amp powermaster unit which is not a direct bolt in as most think. instead they use a gm style case (and gm style 1-wire). this isn't a huge deal though... all that you need to do is fabricate a bracket... i got a universal alt bracket from the local parts store for $10 and by using that and my stock bracket i had a bracket that worked in about 20 minutes. althought it sucks that i had to make a bracket, the good part is that if i ever have a problem w/the powermaster out in the middle of nowhere (where only gm parts are sold) i can get any 1-wire gm alt and bolt it in...

[MitchB]

Maybe not the info you are looking for, but I converted my 1980 Aspen to use a 78 amp Mopar alternator with a Ford external voltage regulator. This reguired running a wire off one phase of the stator winding to the field terminal of the regulator. This is an easy modification. This charging system works excellent.

Mitch

[ehostler]

Originally posted by rebby
... the good part is that if i ever have a problem w/the powermaster out in the middle of nowhere (where only gm parts are sold) i can get any 1-wire gm alt and bolt it in...

Then why pay all of the extra money for the powermaster, if you can go to the auto parts store or auto salvage yard and get a GM 1-wire unit??

Again, I would go with the new 130 AMP ND (from a Dodge conversion van) on ebay, before I would ever consider putting a GM unit in my car. It can also be replaced by ANY parts store.

[charger_dan]

dkn,
I picked up the late-model square back alternator, elec. regulator, and even the correct factory-style regulator pigtail from NAPA for not too much money. Wired it up, and it's been totally reliable ever since. Go for it.

one other thing:
It's also a great point to check the condition and current carrying capability of your existing battery lead off the alternator. I ended up replacing my stock gauge stuff with I believe 10 gauge, along with all new field / regulator wiring. You might ask some other guys what they recommend for wire gauge vs. amp/load rating.

Good luck!

[ehostler]

Anything above 55 AMP will need a 10 gauge cable that wires directly to the battery (or where it connects to the starter relay or starter motor). This is because the under dash wiring and the stock alt gauge cannot handle that much current.

I didn't know that anybody carried the connector pigtail for the '70 & up regulator. I'll have to check my local NAPA and see if they are still available.

[ehostler]

Cool... I found the regulator connector on the NAPA website. It is Item # ECHVRC38 and it is $7.49

[rebby]

Originally posted by ehostler


Then why pay all of the extra money for the powermaster, if you can go to the auto parts store or auto salvage yard and get a GM 1-wire unit??

good question... unfortuantly my only answer is ignorance and misguidance by a sales person... i was told "this is a direct bolt in for a bb mopar". turns out that it isn't...

[dkn1997]

rebby, that sucks- I hate that s%$&- "direct bolt on" and they still made you fab up some brackets!

I am leaning towards the 78 amp mopar unit. That one on ebay is a steal at 75 bucks, but I do not know how easy it will be to swap pulleys. I am not sure how to do it and when I replaced my original two years ago, the new on had a double pulley on it. I wanted to switch to my stock single, and could not find a machine shop who would press it off/on for me.

Is this some easy procedure that I just do not know about? and do I need to find a new machine shop?

[ehostler]

The unit on ebay uses a bolt on pulley, not a press on pulley. You would need to get the correct pulley from a '70s MOPAR or a GM.

[dave571]

No need to change up the regulator to the new style.

The Wilson replacement, for the old style regulator( that looks exactly like the old one, and is a direct bolt in), is electronic. Open it up and have a look, if anyone doubts me. They sell up here for about $14 canadian(8.50 us money) If, you've changed your's in the last few years, it's probably elctronic already. Pull off the cover. If it looks like a relay inside, it's point style. If the bulk of it is empty, with a little circuit board in the middle, it's electronic.

No connector or rewiring needed, when going to the newer alt. Just ground the second terminal on the alternator. The difference between the pre 70 charging circuit,and the post 70, is the location of the regulator. In the early cars the power side(of the field current) is regulated and the ground is direct. In the later cars, it's direct power to the first wire, while the second is the ground(and goes back to the regulator to be grounded)

Field current flow works in exactly the same way. Again, if there are any doubters, get the factory wiring diagrams and compare. Or take apart the two alternators. The second brush goes straight to ground. In most of them this is visable without even dissassembling the alternator. Just look at the back of it.

I've done this many times, and have always been confused as to why the newer regulator is more appealing. The old one works fine, and can be replaced with an electronic unit cheaply.

Ps. You should be able to get the 78 amp from a parts store(with a warranty) for the 75 bucks or less(I know they're about 75 canadian around here..50 bucks us money?). Ask for one for an 1980 dodge truck or so. They are listed in the catalog, by amperage and by double and single groove pully. Any parts man should be able to figure it out for you. At the very least, there should be one guy in the store who can read the book.

If your looking for a high amp one at the wreckers the difference is obvious. The windings(between the case halves) are only about an 1/8 of an inch thick. The ones on your old style one are more like 1/2" between the case halves.

[George G. Leverette]

Dave 571 thanks for the explaination on the differences between the thick vs thin stators are, heard a lot of references to the thin\thick stator but no way to indentifiy them. What about the small diameter alternators found on some of the later cars do they have the same 60 amp output?

[dave571]

I'd have to look in a parts catalog to be sure. I'm not sure of the amperage changes year by year.

I know that 78 amps were quite common among the later years of v8 car production.

If you are near a Napa, ask if they will let you look at one of thier catalogs. For that matter, they should be willing to give you one if you ask. They don't cost the store anything, and they are commonly given out to repair shops. So they can look up they're own stuff when problems arise.

[dkn1997]

Hey guys, thanks for all the great input. Some last questions(hopefully):

1. If I go w/ the chrysler 130 amp job, where would I get the correct pulley?

2. Do I have to eliminate my amp guage? I seem to remember reading in car craft that they way it is wired into the charging system (series) blows anyway, and that w/ a really high amp alt, would not hold up. Has anyone ever run into this?

My general plan seems to be to get the alt, pulley, reg and plug. Then add my field wire and replace my + wire on alt w/at least 10 guage and possibly eliminate the amp guage and replace w/volt gauge.

[ehostler]

You would leave the normal + wire in place. Add a second + wire of 10 Guage, going from the alt to where the battery connects to the starter relay.

With the 130 AMP unit, you will ahve to come up with a different way of securing it on the bottom. The factory style has a bolt that goes into the case. This alows you to hold the alt tight while using the other hand to tighten the bolt into the case. You'd probably be able to overcome this with a nut on the bottom hole of the new alt.

[dkn1997]

Ok, here we go. Just bought that ebay alt for $75 and it will ship this week to me. Just have to go to the napa website for the plug. (tried the store, what a waste- "um...what year car is it for?"
I even had a part #, and they could not help. Anyway......

I hope to tackle it this weekend, but one last thing- do I have to eliminate the stock amp gauge, or will it hold up?

[ehostler]

If you run the second + wire from the alt to the where the battery connects to the starter relay, there is no need to disconnect the factory AMP guage.

[ehostler]

In order to find the PN on the website, I think that I told it that it was for a '74 Duster. It wasn't listed for a '74 Challenger. I agree that it's kind of stupid that they couldn't find it with the PN.

I know when I bought my last set of spark plugs (for my Ram), I wanted to change the heat rating. As it wasn't listed in the computer for my truck, they wouldn't sell them to me. They did have them in stock, on the shelf, but refused to sell them to me. Sometimes the NAPA policies leave a little to be desired.

[dkn1997]

ok, I got all my new stuff:

new denso 130 amp mopar alternator

new napa reg

new plug for reg.

I still need to get a pulley for it and will try this week to get it.
Also, saw female socket on back of new alt with two terminals. I assume these are the field terminals??? that's what they look like.

I have decided to bypass the amp gauge and bulkhead fitting and install some fusible links as per the info on the mad enterprises website. I do not want to toast this thing!

the old alt is so bad. had the car out this weekend and would barley charge at idle at all. only reading 12.2 V at bat w/engine running at idle. has been getting progressively worse over last month

Anyway. thanks to all for input and I will let you know how it goes.

Kevin

[ehostler]

Yes, the two pins in the oval connector are the field connections. You can eithier try to find the correct connector or fabricate something.

As far as bypassing the ALT guage goes, there really is no reason to do so, if you run a 10G wire from the Alt to the starter relay (where the battery connects to it), in conjunction with the existing ALT wire. In that configuration the ALT guage will take a very minimal load, as most of the current will be going directly throught the ALT wire(s).

[dkn1997]

I will try to locate that connector for the fields, but will probably end up using two female spades or something similar.

I will try to run just the extra 10 guage, I do not want to have to change all that other wiring unless I absolutely have to.

I am working on the pulley, and then I will be good to go. Also, amazing how small the new alt is. Looks it will bolt in with just an extra bolt/nut on that lower mounting point like you said.

t hanks, Kevin