installing a 100amp alternator

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Zuluman

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I have purchased a 100amp alternator for my 1975 Plymouth Valiant and the necessary upgrades to the wiring has been done. It seems the 100amp alternator needs different mounting brackets and hardware. Can anyone suggest where I may purchase this ?
 
what alternator did you buy?....kind of hard to make suggestions went we dont know or see what ya got........
 
The huge 100amp factory alternators found in C-body applications do require different brackets. There are other 100amp aftermarket units that look just like the stock alternator that do NOT require different brackets.
 
.................Not sure why guys want to do this, is this actually in an A body? Remember this: These have, relatively speaking, HUGE rotors. Just about any rotor is geared (pulley ratio) 3:1 or 4:1 above crank speed so if you are spinning the engine to only 5K that alternator sees at least 15 THOUSAND RPM!!!!

I used to run one of these when I had the "wench" on the old FJ-40, but I wouldn't want one my my Dart
 
Police cars from the 80's had them on 360's. Someone on FABO should have them. In all my years working on Chryslers, I have never seen a 100 amp fail.
 
Don't know if it's the same but I put a 100 amp alternator on my '69 cuda (318) so that the battery could keep up with the 500 watt stereo system and the electric fans for the radiator. Bought the alternator at O'rielleys.

Treblig
 
Pickups with a winch or snowplow would be another good place to look for the brackets that fit the 360. My old 77 W150 had one. Are there any salvage yards with old Dodge military vehicles near you?
 
Gentlemen, thank you for your feed-back. I bought the alternator from "Parts Train". Here is a link to the part.


http://www.partstrain.com/store/details/Plymouth/Valiant/USA_Industries/Alternator/1975/Custom/6_Cyl_3-dot-7L/US7521.html


It is supposed to be a "direct fit", but it is not. I have 2 solutions ; find a 100amp alternator for my car or the mounting hardware for this one. I'm indifferent between the 2 solutions because I must spend money either way, but I prefer to take the advice from this community rather than rely on the claims of vendors.

In either case I would appreciate a link to a vendor. A breaker's yard is not a good option. I live in France and we don't have many old Mopars in breaker's yards.


The wiring has already been upgraded to cope with the amperage.


I need a 100amp alternator because I have a great deal of non-factory electrical and electronic equipment on my car, including an electric radiator fan that draws 27amps at full power. My Valiant also has 4-wheel disc brakes, 4 wheel coil springs with adjustable dampers and rack & pinion steering, so it's not very original. My apologies to those among us who are purists..
 
That most definately is the Mopar "large frame" alternator. As mentioned above, stuff like police cars, W series pickups, etc and other "big cars" are good candidates. One complication that will problably enter into it is AC

It SEEMS to me that I was actually able to modify either the brackets or alternator and got it to fit........had one on a small block in a Landcruiser (with a wench LOL)
 
.................Not sure why guys want to do this, is this actually in an A body? Remember this: These have, relatively speaking, HUGE rotors. Just about any rotor is geared (pulley ratio) 3:1 or 4:1 above crank speed so if you are spinning the engine to only 5K that alternator sees at least 15 THOUSAND RPM!!!!

I used to run one of these when I had the "wench" on the old FJ-40, but I wouldn't want one my my Dart

If you add electronics and accessories like radios, electric fans, high output ignition systems you need the extra juice from a higher output alternator. That's why :)

The wiring has already been upgraded to cope with the amperage.

When you say you "upgraded the wiring" do you mean you installed larger gauge wiring or that you have eliminated the amp meter and the bulkhead pass-through? The only reason I ask is because if you are still having the alternator output go through the bulkhead connector, when the alternator reaches full output, it definitely will start a fire at the bulkhead connector. I'd hate to see a Mopar go up in flames.
 
If you add electronics and accessories like radios, electric fans, high output ignition systems you need the extra juice from a higher output alternator. That's why :).

I'm aware of that yer sillyness. What I'm referring to is this particular unit, which is huge, giant, monsterous, and when used on a high performance high RPM engine just might come apart from together. Read the rest of what I wrote.

.................Not sure why guys want to do this, ....................Remember this: These have, relatively speaking, HUGE rotors. Just about any rotor is geared (pulley ratio) 3:1 or 4:1 above crank speed so if you are spinning the engine to only 5K that alternator sees at least 15 THOUSAND RPM!!!!

I used to run one of these when I had the "wench" on the old FJ-40, but I wouldn't want one my my Dart


There are much much more compact and better designs out there nowdays than these huge anchors
 
I'm aware of that yer sillyness. What I'm referring to is this particular unit, which is huge, giant, monsterous, and when used on a high performance high RPM engine just might come apart from together. Read the rest of what I wrote.


There are much much more compact and better designs out there nowdays than these huge anchors

ahhh now I sees what your getting at. I purchased a Powermaster alt. that is relatively smaller in size than even the original alt. that came on my slant. Might be worth a look at for the OP.

I have purchased a 100amp alternator for my 1975 Plymouth Valiant and the necessary upgrades to the wiring has been done. It seems the 100amp alternator needs different mounting brackets and hardware. Can anyone suggest where I may purchase this ?

Also, I bought a summit mounting bracket for my Powermaster Alternator. not sure if it will work for that alternator or not, but I don't believe it was made for the Powermaster either. It seems to work fine for me.

http://www.summitracing.com/parts/sme-2006/overview/
 
Thank you, gentlemen, for your input. It is most appreciated. Yes, I have had the ampere meter modified to be a volt meter and upgraded the wiring to a thicker guage. Although I paid only € 450 for my car at the breaker's yard, I've probably spent more that € 40K building it so, I have a big investment to protect.

Thank you, 71Scamper, for the link.
 
Thank you, gentlemen, for your input. It is most appreciated. Yes, I have had the ampere meter modified to be a volt meter and upgraded the wiring to a thicker guage. Although I paid only € 450 for my car at the breaker's yard, I've probably spent more that € 40K building it so, I have a big investment to protect.

Thank you, 71Scamper, for the link.

welcome
 
Thank you 68GTXman, for the informative link. I now know exactly what happened to my 1978 Moskvitch 412 and can make the necessary adjustments in the wiring loom for this car was well.
 
I bought the same beast alternator on ebay a few years ago. It looked much smaller in the photo. Thanks for the info on maybe needing different brackets. I doubt I will every use in my cars, not after I lifted the thing. I need to find a guy with an old Mopar tow truck to sell it to.
 

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