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My alternator is toast. Recommendations on new one?

manic_mopar

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So as i'm finishing up my front end after having to pull my timing chain cover, I go to install my alternator with my new arp bolt kit from 440source with the spacers and all. They didn't fit like the janky rusted spacers I had. I noticed that one of the 2 main mounting holes for the really long bolt had a steel sleeve pressed into the hole and it was left a little too long, keeping the spacer from sliding in between the two holes. So i pressed the spacer out the other way and noticed the hole was cracked all the way through! Investigating further, I pressed the sleeve out, and upon seeing another hairline crack, i played with it with my plier and it snapped right off. I'm glad i discovered it now and not driving down the highway.

So now I'm in the market for a proper alternator. That one was 20+ years old and i'm not mad about it going. What do yall recommend for a 440 stroker with dual electric fans and a full ignition system from FBO. Is 60 amps enough? I haven't started the car with the new dual fans yet. Should i consider going bigger? Is internally regulated vs externally regulated worth investigating?

Any insight is helpful! Thanks

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With 2 electric fans, I wouldn't hesitate to go for a higher amp unit. How much more depends on how much your fans draw when both are running and even add to that having lights and other things on,(wipers, radio, a/c, etc.) I have 2 electric fans and even with nothing else on at idle, with one fan my voltage drops to about 13 volts, when the second kicks on it drops to about 11 volts. That said, I had already upgraded my stock alternator to a 95 amp Power Master which I would recommend as a minimum. I have to step slightly on the gas to raise the rpm's to compensate. If one was available,(and there isn't), I could put a smaller pulley on the alt but that's a dead end. I will be looking for a Denso or something that can deliver more juice at idle. Perhaps one with a built in regulator. Other than that I am quite satisfied with the Power Master that I got from Summit! Good luck!
 
Get an alternator from a mid 80's dodge truck or van. Looks just like the older square backs but charges great at low RPM's. The one in my 68 coronet gives me 14.3V at 800rpm... I think it's rated at 90A. ...
I can't get the correct one in my 70 dart to charge for crap under 1000rpm.... pisses me off at night with the lights on and sitting at a red light, lights go very dim...
 
The new 95A powermaster I installed recently seems okay at idle speed, even with all electrical items on and the new 2 speed derale 17" electric fan on at full speed. I'm finding the voltage a tad high while driving though at 15v. I plan on changing the volt reg to the new style even though the old one is an electronic version of the original style.
 
I have all new wiring for the engine harness, dash harness, rear light harness, forward light harness. I went wiring crazy last year, it's all the M&H stuff from year one.

I'll take a look at the fans i got ( its from cold case here on the forum) and see what draw they have.

If i go with a 100A +/- alternator, do I have to beef up any wiring going from the alternator to the firewall or up under the dash? Are yall bypassing the factory dash ammeter? I just want to make sure i'm not gonna have a meltdown when the car fires up. lol Thanks.
 
Get an alternator from a mid 80's dodge truck or van. Looks just like the older square backs but charges great at low RPM's. The one in my 68 coronet gives me 14.3V at 800rpm... I think it's rated at 90A. ...
I can't get the correct one in my 70 dart to charge for crap under 1000rpm.... pisses me off at night with the lights on and sitting at a red light, lights go very dim...
are you pulling from a junkyard, or ordering one new for that generation of van/truck?
 
Got mine from napa and had my local alternator shop go through it and replace any of the cheapo pieces inside. Do you have an alternator/ starter rebuild shop ? They usually have a bunch sitting on the shelves, that's where I get my factory gear reduction starters from for my old mopars.
 
JMO
If you do upgrade to a 100 amp I would increase the wire size #10@ min, 8 would be better and solder the connectors instead of crimping, I would also run it sraight to the battery.
 
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So when yall do this alternator upgrade, are you guys following the MAD ammeter bypass from http://www.madelectrical.com/electricaltech/amp-gauges.shtml ? Is this a pretty good guide for doing this? I Have all brand new wiring in the car including the bulkhead, so i'm not too keen on drilling holes in my new bulkhead. But I definitely want to delete that ammeter and just hookup a voltmeter somewhere, or even grab one of those cigarette lighter voltmeters.
 
Yes, follow the mad electrical upgrade. And don't drill holes in your firewall ! I removed the 2 factory 12g power feed terminals, drilled straight through the bulkhead connector utilizing the factory wire location. Feed the new 10g wire through the connector and leave enough slack for future service !
 
Ok then I guess ill pull that main bulkhead off the firewall and drill it out. Sounds like i may need to go bigger than a 10g wire. IllIbe doing either the 100 or the 130 amp tuff stuff alternator. I like their fit and finish. And allegedly, according to themselves, they have good low rpm output.

Thanks for the help yall.
 
Oh! I almost forgot, do we still leave the wiring from the dual field connections coming off the alternator that go to the voltage regulator? I think ill be getting the tuff stuff voltage regulator to go with the alternator. Those wires we dont reroute, delete, or otherwise change right?
 
Bigger than 10g ... how much stuff are you running ? 100a alternator will only put out as much as needed .. electric fans, electronic ignition, radio and lights only draw so much. Unless you're running all those items plus A/C, you won't come close to that alternators rated output.... I think 10g will suffice, but that's just my opinion
 
I appreciate the input. Ive got a full sound system w subwoofers that are disconnected right now, but i forgot that even when i hook it all up, itsiall on dedicated lines to the battery. So youre right, for core system draws, the 10 gauge should be plenty. I do plan on installing AC next year.
 
Size you wire accordingly make sure a 10 will support your needs. Later on if you realize that you have more load than is comfortable you can come off the battery with fused circuits and let anything coming from the fuse block control a relay to switch that circuit that way you keep the current running through your bulkhead and fuse panel to a minimum.
Like I said earlier if you are going to use #10 solder your connections. DO NOT USE PLUMBING (tin/lead type) SOLDER!!! You want rosin core, otherwise you're joint will corrode, overheat and eventually fail.
Also since you will have your bulkhead apart it would be wise to coat the terminals with an anti oxidant like NOALOX.
 
I have a 120 amp conversion kit complete with a new reconditioned alternator for sale if you're interested. It fits B or RB engines.
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Thanks for the offer andy! I actually ended up ordering a Tuff Stuff 1-wire alternator.
 
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