Alternator questions

Are there any alternators with higher amps that are a direct fit to our B's? I know some people use windstar alternators or early '00 gm models, just curious what one in particular that i should try and get or would any one i choose require re-wiring and mounting brackets?

I just put in a GM 76-83 vehicle year 105amp (ebay) alternator in mine took about a half hour. But mine is 3 wire 1 bigger gauge to the battery and 2 at the connector (EFI). If it is carb'd I think you need a 4 wire 1 bigger gauge wire and 3 at the connector for the choke, batt light and VR.

I just had to drill out a bigger hole and mount it upside down, widen my stock tensioning bracket with a grinder and solder on a new connector that was $2 at the parts store. Oh and I needed a thinner belt... easy. Plus i added a 4 gauge wire from it to the batt. Not sure if it will work for carb'd models though. Maybe you can use the choke off a different circuit?

This alternator was 70 bucks and provides plenty of amps with my HIDs, LED bar, sound system, heater all running. I have a bunch of pics from the install on my camera at home that I can do a write up on maybe this weekend some time if you want...



You could do a GM 1 wire but I like having the idiot light and reference for the Voltage regulator so I don't have to "excite the alternator" like in a 1 wire setup.

I have a 929 mazda alternator in my 88 B2200 with a weber. The counter person swears it pumps 100 amps. Bolts right in and the dash board idiot light plugs match the rear of the alternator. The only problem is the weber choke wire plug is not available on this alternator. I assume it's because the alternator was for a 929 EFI setup engine. So far no problems I've had it for over a year. My morning start ups are not an issue to the weber and the temperature is basically the same every day. It will still start up in a few timed cranks if I didn't drive it for a couple of days.

Appreciated Cab+Driver, and Spacemonkee, i had seen the 1 wire gm alternators on the advance site, very nice ampage i think up too 120, have look be sure, but not very concerned about the idiot light, the alternator tested good twice, and even after i removed my amp and foglight hookups it still happened and wont start.

Now, my next question is, what is the 1 wire gm alternators exactly? I have never seen or used a 1 wire alternator so kinda something new to me. would it just be connected to the battery terminal? Or would i have to mock up a ground to it?


( EDIT ) just re-read your post Spacemokee, when i removed mine i had only 3 wires, one with a nut holding the power wire on, and two connectors, one to my choke and the other the dummy light i assume? and excite the alternator? As well I don't have a voltage meter just the dummy light.

The three wire setup was simple with mine... I have EFI so it may be different for you. The wire w/nut goes to the battery + (I used 4gauge Amp wire - extra from my sound system) and the other two at the connector are 12V constant and 12V ignition. Its was as simple as that for me, Just a little bit of drilling and grinding to mount it up plus a little soldering. I'll try to post some pics this weekend.

1 wire alternators use a different charging method. With the 12v constant and 12v ignition plugged into a 3 wire, the alternator uses those signals to know when to start charging and when you turn on the ignition. With 1 wire setups there is no reference voltage to tell it to start charging other than it is spinning, so when it reaches a certain RPM it recognizes or "excites" the alternator it and charging begins. I think with the higher the amperage the higher the "excite" RPM is... Or at least that is my understanding of it... I'm sure someone on here can explain it better (or correct me).

Ah okay, and well i don't have a soldering gun atm, had chance get one cheap while back pro should have. lol but oh well and pics would be helpfull. as of right now i'll prob leave her sitting for little while, pickup nice high ampage alt an new battery n see where that takes me.

Also I think i posted or asked this in another thread about this, not sure kinda early lol. But if say i per chance ( good chance lmfao) on installing foglights, then amp wire under the clamp on my battery post clamp, and not gotten all the wires in correctly ( Far enough or snug enough) would this cause my battery to slowly drain over time? Or if wire just worked its way loose cause of it not being in good enough. because i had no previous issue for over a week after installing the amp and foglights like this, i'm thinking maybe over that period it slipped out or just suddenly did running me straight from the battery draining it, and if so, if i get it running and let it sit or drive about for a while with no stereo or anything on would this re-charge the battery or be better off with a new one?

Its hard to say without being able to see it... but if I remember correctly, your fog lights were disconnected by the previous owner before you got it... maybe they were disconnected for a reason, and now that you have hooked the wires back up it is causing a parasitic drain when the truck is off? Just a thought.

Check all the wiring or just take all the fog light wiring out and re wire them correctly as I recommended to you on your fog light/ toggle switch thread - all those MS paint diagrams ... and as I said before "Don't ever trust aftermarket wiring jobs" by "professionals" at shops or previous owners I only trust my own wiring jobs because then I know its done correctly.

Good Luck.