Alternator options

[Kern Dog]

I think it is fine now.
The battery in the car is an Optima and it seems that when they discharge, they take a while to fully REcharge. I wasn't driving it enough for the alternator to have enough of an effect. I was using a small charger on all my batteries, a unit I have had for over 10 years. After seeing that three batteries failed to fully charge, I suspected that the unit was faulty. I bought a new charger, a bigger one with wheels. It fully charged the Optima and now the car seems to be fine.

 

[Nacho-RT74]

I'd say the pulley size is a year change after they began to take care they were unnefficient. thats all.

A/C compressor also changed the pulley size, in between 69 or 70 I think ? no matter the engine, but the year.

 

[Sweet5ltr]

On any other manufactures vehicle built during this time period, I would say run a 180-amp (+) alternator if upgrading. I don't know, with forty year old wiring and the bulkhead issues these cars have, I went with an AR engineering bracket and a simple 60-amp Bosch (Denso) alternator. I don't want to risk my car burning to the ground recovering a discharged battery, I would personally stick with a 70-90 amp alternator. Check out the alternators performance curve, you'll want to estimate how many amps your current system draw is, verify pulley ratio, and idle engine speed. I'm idling at 1,200 RPM so i'm not too worried, but it may impact someone whose engine idles at 750 rpm.

 

[wyrmrider]

Dog
have you done the amp gauge bypass lots of articles on this so google
and relay on the headlights
dbl check the grounds

 

[Kern Dog]

Dog
have you done the amp gauge bypass lots of articles on this so google
and relay on the headlights
dbl check the grounds

Yeah, I replaced the bulkhead spade connector with a continuous wire from the Starter relay with a fusible link in between. There is no ammeter anymore, I have a Dakota Digital gauge cluster with an amp gauge. I sort of followed the MAD electrical guidelines but did it slightly different. I also changed over my 75 Power Wagon. Next up will be my Brother-in-laws 72 Duster.
No headlight relays yet. In 2013 when I tried to use them they screwed with my headlight doors. I just found out on this site recently that there is a fix for that.

 

[RoasterStrudel]

Not sure if anyone cares, but I put a Tuff Stuff 100A on my car and idle output was no better than the 60A parts-store unit it replaced. Wanted to run the stock style alternator due to serpentine setup bracketry. Also the positive diode pack zapped the first week I had it (rotor was out of round, shorted inside and had to be clearanced). Powdercoating was nice, though.

I believe many of the 130+ amp "one wire," units you see available are typically GM style. It's either those, or the fancy billet pieces you see from Flaming River, Mechman, (costly, but look nice) or Quality Auto Power (which look questionable).

I think it's more or less a Mopar design thing. I know my output wouldn't really keep up until well into cruising RPM.

 

[Kern Dog]

Your screen name is funny.

 

[Nacho-RT74]

Not sure if anyone cares, but I put a Tuff Stuff 100A on my car and idle output was no better than the 60A parts-store unit it replaced. Wanted to run the stock style alternator due to serpentine setup bracketry. Also the positive diode pack zapped the first week I had it (rotor was out of round, shorted inside and had to be clearanced). Powdercoating was nice, though.

Well that's something allways could happen on any unit. The beck arnley alt from Rockauto I bought barelly hold 1 year or so ( rotor said bye ), just that being overseas I have no way to fill a claim in case of an early failure. I knew somebody with a similar case with a TuffStuff alt and got inmediatly change without questions from Summit. So there is a customer backup on the product.

I think the tuff stuff alt you got got a factory fail and that's the reason for the same output than a 60 amps unit? Maybe.

 

[Nacho-RT74]

Dog
have you done the amp gauge bypass lots of articles on this so google

No need for that if you take care if the stuff around....

 

[wyrmrider]

dog- I had been using the extra spade relay- and maybe found out there was a reason same as you did
you ight post up those links
cheers

 

[Darius]

Today I ran the car in the garage/shop and once it was up to temp, the voltage was at 14-15 at idle. I turned on the headlights and it momentarily dropped to below 13, then went back to the 14 range. I pressed the brake pedal and it dropped to around 12 and stayed there. I'm surprised that the brake lights seemed to draw more power than the headlights. Regardless, the voltage output seemed okay as compared to how it was a few days ago. It increases nicely once I am over 1500-1600 rpms. Maybe I don't need a new alternator. The A/C crank pulley I'll be using is a 7 1/4" unit, the current NON A/C pulley is a 6 1/2". The larger pulley is about 11.5% bigger, making the alternator turn faster. That should help it at idle.

Hey Greg
Dean says he had the same problem with low charging on an alternator that came with a March pull set up (I have one also). We were looking at mine the other day and he tells me he changed the pulley and it solved the problem so that may be a cheaper fix for you. We are going tom change mine when I get back from Spring Fling

 

[747mopar]

My current serpentine setup will do the same if I idle it down to much, it's right on the fence where a slightly bigger pulley would fix it. In my case it was just a matter of raising the idle rpm just a hair and I mean a hair.

I first noticed it sitting at the Canadian border forever with the A/C on, voltmeter slowly dropped to 12 (normally 14) so I just barely sat my foot on the pedal and up it went. Normal day to day driving would never show it because there is no traffic where I'm at so it was never even noticed since I'm reading volts not amps.

 

[Nacho-RT74]

My current serpentine setup will do the same if I idle it down to much, it's right on the fence where a slightly bigger pulley would fix it.

I guess you meant bigger crank pulley? because on alt would need smaller.

 

[5.7 hemi]

You could always do the Denso alt upgrade, small, single and double pulley set up.

 

[Kern Dog]

The last couple of days it seems fine once the engine warms up.

 

[747mopar]

I guess you meant bigger crank pulley? because on alt would need smaller.

Thanks for picking that up, yes I meant smaller.

 

[Xp29h]

Nacho.. beat me to it on tuff stuff. That’s what I put on this winter and working great..

Got off summit

Good luck