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Does anyone run a higher output alternator on their 71-74?

USatC

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I’m getting my ac working and i’m worried my system will have issues running with the lights, ac, speakers, etc. on my 60amp alt. Has anyone used the 114 amp alternator most parts stores are selling now? Do they bolt right up and what needs to be upgraded on a stock electircal system to support that amperage?
 
This is the alternator.

79947823-C751-4CCD-A2DF-1C6E2B3711A3.jpeg
 
When i owned this 71 Cuda i installed on of those 100 amp alternators off a later 70's fleet vehicle.
It worked well, but you need all the bracketry for either big block, or small block engines.
Another thing, they are heavy.
If your worried about weight, then they are not for you.
Now a days, these alternators are pretty outdated, and there are better alternatives, but i can't give you any information, as i haven't done a swap like that.

Picture 022 (Small).jpg
 
I don't know what the alternator in the photo is? Have more info on it? Is it still externally regulated, or internal regulated.
Quick and easy wiring update is to just run an extra alternator output power wire of about 8AWG from the alternator output stud to the battery (with a fuseable link.) This would be in addition to (In parallel) with the stock wiring.
 
and what needs to be upgraded on a stock electircal system to support that amperage?

The extra amperage won't ever be a problem BECAUSE the alt gives what the car needs. You can get a thousand amps alt, but if the car needs just 40, the alt will provide JUST that. If the batt gets at certain point discharged and begin to suck 15 amps, the the alt will provide 55 amps in total, where the ammeter will read just 15 because the initial 40 amps are before the ammeter when engine is running, so ammeter won't sense that. The ammeter just reads what leaves and return to the batt, not what the alt provides.

http://www.dodgecharger.com/forum/index.php/topic,33574.0/all.html

You need an alt able to provide all the juice as posible while iddling, no matter the max output ( of course it is common the more max output you get, the more juice is able to give at iddle ). When you get that, you will find how dark were the old days LOL And how safe will be your wiring system. If you are able to find the iddle specs for an alt and match that with your car, better. The car needs barelly changes between iddle and high RPMs
 
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The extra amperage won't ever be a problem BECAUSE the alt gives what the car needs. You can get a thousand amps alt, but if the car needs just 40, the alt will provide JUST that. If the batt gets at certain point discharged and begin to suck 15 amps, the the alt will provide 55 amps in total, where the ammeter will read just 15 because the initial 40 amps are before the ammeter when engine is running, so ammeter won't sense that. The ammeter just reads what leaves and return to the batt, not what the alt provides.

http://www.dodgecharger.com/forum/index.php/topic,33574.0/all.html

You need an alt able to provide all the juice as posible while iddling, no matter the max output ( of course it is common the more max output you get, the more juice is able to give at iddle ). When you get that, you will find how dark were the old days LOL And how safe will be your wiring system. If you are able to find the iddle specs for an alt and match that with your car, better. The car needs barelly changes between iddle and high RPMs
A little late too this post. I have replaced the dash harness, as well as all the wiring in my 1967 plymouth belvedere. The instrument cluster was rebuilt by instrument technologies, and replaced the ammeter with a solid state limiter. I will use a mopar electronic distributor. I am not running any power windows, crazy amped stereo, no power seats. Down the road i may go with an AC system Vintage air etc. Will running a 70 amp alternator turn my mopar into a carbecue?
 
Your car will suck the same having a 70 amps or a thousand amps alt. The difference is if the alternator is really able to provide what the car needs at the minimum speed as posible. If not, the batt will begin to be sucked up. That's when we have had for years the swinging ammeter needle giving gas or not ( increasing alt speed so then a batt claimming back what lost previously) which is the unnecesary job on it.

An alternator will not toast anything really, but the “bogs” on the charging balance system, and its conditions will.
 
Accesories can become on a failure if you source them from batt. That will add stress on system and a incorrect amm reading. Accesories must be sourced on the line between amm and alt, just like factory did building the main splice. Of course if you don’t have an amm anymore won’t matter anymore. But good conditions wiring and conectors is still needed.
 
Yes I used an M&H dash harness, all the wiring is stock type wiring. I used all factory connections with dielectric grease, and all grounds were connected, and I did grind down to bare steel for the grounds. I did not slice, and dice any of the wiring while installing. Plug, and play just like the factory. I thought about Ron Francis or painless or other companies, but was not comfortable attempting that. I also used a headlight harness with relays which I bought from crackedback (on this forum)
 
Failures, power decay due bad contacts, bad wiring
"Bogs"?
That’s not an electrical term I’ve heard used before; can you elaborate a bit? Are you referencing higher than normal resistance at old electrical connections, bulkhead ? Creating heat and/or voltage drop?

New exact replacement wiring harnesses will not address the original undersized charging circuit wiring or the routing of the charging circuit through small Packard connectors at the bulkhead. Adding additional electrical loads certainly won’t help that either. Replace 12 gauge charge wires with 8 gauge, route directly to the ammeter, by-pass the bulkhead completely for those circuits.
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"Bogs"?
That’s not an electrical term I’ve heard used before;

Yeap I know LOL. That’s why I used “ “ LOL

I meant those misterious electrical failures nobody knows where it comes because the ignorance about the electrical system, and of course caused by what you mentioned which translate on constant discharge readings, flickering electrical devices, overcharge...

And in ANY CASE, never caused by a high alternator output rate by itself

Definitely not the correct therm but just wanted to called in some way. LOL
 
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