3-Wire to 1-wire conversion, what do I have to do?

I am thinking of buying the "Mr Amp" alternator for my 79. It produces 65 amps at idle which is what I need to power the spal fans I have. The stock alternator can barely charge the battery when its idling.I am reading about 12.9 volts no fans and 12.5 with fans. So this is going to be a necessary upgrade, a high amp alternator that is. In either case I will be converting to EFI and adding a lot of ther electronics in the future so this is going to pay off in the long run.

My question is how hard is it to convert from the "3 wire" which is what these things came with right? to a "1 wire"?

Will the conversion from 3 wire to 1 wire be necessary for my future plans? And should I just do the conversion now?

Does anybody have any other suggestions for other alternators that produce high amps at idle?

Thanks for the help

Frank

p.s. I reposted with a different subject to get more attention/help

[Bullitt]

Hey Frank, how much are you going to spend on that alternator? My friend has a new chrome 1-wire lying around. He sold his car and has it left over. It's in the 60-65amp range. If you're interested in it, I'll see exactly what it is.

--Bullitt

[page62]

At least for now, the battery can handle the load when you're at idle. The alternator will recharge the battery when you speed up (kinda like one of those hybrid cars...)

With regards to the 1-wire conversion, I'm not exactly sure, but I think it's easier than you think. Check with the vendor and see if there's any supporting documentation.

[cruzer99]

The single wire alternator is internaly regulated so you only need to connect the battery lead to the alternator. The other wires are not used. If the alternator came with a new connector, replace the old one with the new one.

Thanks for the offer Bullit, but I already have a 65 amp alternator. He he he thats the problem

So basically I just need to plug in the postive lead from the old alternator to the new one, and just not connect the negative lead and the other (third wire) wire?

I found another alternator that will just bolt in, no converstion, BUT it produces 14 amps at idle. The fans need 25 amps to run properly.

[cruzer99]

You could cut the unused lead off if you want.

Shop around for a 100 amp. You usually can find them at any street rod shop or show. Only one warning, many of the 100 amp alternators are just rebuilt and don't put out the advertised amps. Chrome ones will go for 85.00 to 110.00.

I am still confused about the specifics of these alternators. So I have taken pics of my alternator to confirm what I don't/do have to use.

In the pic
1. Is the positive lead of the alternator
2. Negative lead
3. Something I don't know what it is

So what is number 3?

From my understanding, with a 1-wire alternator all I have to connect to it is the positve lead (1.) and the negative (2.) and wire 3. are not used right?

Why is the negative not used, because its already ground with the bolts or something?
3. is the connection for the regulator right? Because these new alternators are internally regualted it is not required right?

Is mine a 3 wire, I would assume yes but need confirmation

He he the mess on the top left is the new relay that doesn't work according to specs. I haven't bothered to tuck in the wires because I was going to buy a better relay and the new alternator.

[cruzer99]

You are correct about the POS is the only one used. The GND is thru the brackets and the third is just a trigger for the "external" regulator. Your new alternator is "internaly" regulated and will automaticaly trigger as soon as you raise the RPM's to around 2000. This is only needed when you first start the engine, after it is triggered it will act like every other alternator.
Yell if you need more info. Like I said before, get a 100 Amp and make them garantee the 100 Amps.

[AKRAY4PLAY]

cruzer82 has the right idea with going for the 100 amp alternator. you will need all the amps you can get if you go electric everything (water pump, fans, fuel injection, power steering, etc.) on your motor. the disadvantage of a one wire alternator is lower voltage. the line loss (voltage drop) with external regulator alts actually adds to the total output. most regulators are set for 13.7 to 14.2 volts. regulator sees 13.5 volts, and the battery post sees 14.2 volts (numbers are different for every alt). a one wire alt will only put out the amount of the regulator. a three wire will put out what the regulator is set for plus the line drop to and from the regulator, usually around .5 volts. that extra half volt may be helpfull for your fuel injection. just something to look into when picking an injection set-up. general rule of thumb i have been told is the more load, the more wires. sorry if i confused anyone, i will try and find the articles from my research and post them. Brian

[vigman]

#1 Positive terminal ( output stud )

#2 Ground

#3 ( 2 wires ) one is for the feild ( rotor ) to energize the alternator to allow it to charge(+12 with key on) 16 gauge red marked 2 or V on back of alt

... the other line is for the BATT light line goes low/gnd when the alt dies (18 gauge brown)
#1 or L on back.. this line has a 40 ohm resistor ( Nichrome resistance wire in it )

Both should be around 12 Volts!


Vig!

[vigman]

Who did your wiring?

Yeech!


Vig!

Thanks a lot guys for the help.

Well I have narrowed it down to four alternators.

1. East Coast Auto Electric "High Amp" 1 Wire alternator. (Jegs)
a. pt# 358-2007 110A $199.99
b. pt# 358-2009 140A $249.99 (ECA suggests a protection for to much amp for $29.99)
**Fits early style Alt's

2. Tuff Stuff Performance (Jegs)
a. pt# 908-7140B 140A $179.99

3. Powermaster (Summit)
a. pt# PWM-57294 140A $139.99
**don't like the way it looks, its for 63-86 vettes

4. Mr. Amp (D.U.I)
a. 140A $250.00
**rated at 65A at idle

Should I worry about the high amps with all the old wiring? I am going to redo all the wiring eventually but don't want the car to poop out on me after a short run I think if I go 140, which I want to, I have to install some kind of protection. I am going to call all the manufacturers and find out what they rate each of their alts at idle. Idle I consider 700-800rpm.

Who did your wiring?

There is a story about that. j/k

I take the car out every once in a while so that I can stretch her legs. One of these nights I was cruising the freeway with my bro riding shotgun. I was about to get off on the last exit so that I could go home. As I was getting in the exit lane a "ricer" flew by me. I thought well I can exit here OR I can catch the next exit and take a longer way home enjoy the ride and kill this ricer. I chose the latter of the two.

So I line up with this ricer, its late at night and the road is clear for a short run. Absolutely nobody in the way for at least a 1/2 mi or so. We were at the border between Tx and Nm. I pulled up next to his door, he looks over and I hear the buzz of his exhaust go up. HELL YEAH ITS ON, I drop it into third and make short work of this guy. My exit comes up quick and I get off. Shortly after I reach a light and look at my temp gauge, 210 and climbing. I can't hear the fans going and think OH S**T. I reach 230 and quickly pull into a clinic parking lot and shut off the engine. PHEWW!! Ok what went wrong and I'll be damned if there is no light. Me and my bro make a 1/2 mi walk to a circle K down the street and get a flashlight. I figured out the relay was not working so I bypass it, get the fans to turn on and let the engine cool.

Well the next day I turn on the car and the box where the relay gets hooked into smokes up. GREAT its gone. I buy another one that suppose to turn on at 180 but turns on at 220 instead. No good for me and a wire I used was a to small a gauge and fries up filling my cab and engine bay up with smoke.

Ok the point is I didn't clean up the wiring because I was going to have to redo it again AND I found the temperature relay that I was looking for at the very beginning. It's a Painless Wiring relay. The sensor gets bolted into the head/intake instead of having a sensor poked through my new aluminum radiator, which I wasn't to happy about.

Pheww sorry its so long.

Well I bought the East Coast Auto Electric 110 amp alternator and installed it earlier today. That was the easy part. Installing the painless wiring relay was more of a pain go figure. The actual converstion from 1 wire to 3 wire was a easy.

Basically as all to previous posts have stated you only need to connect the postive wire and thats it, you can tie up the rest of the wires. I called the ECAE technicians just to confirm everything that was stated here and I got the same answer. So there you have it.

Performance:
As far as performance is concerned I noticed a difference right away. When the headlights and the dual spal electric fans are going I noticed that the lights were brighter than before. Also on the Voltmeter gauge when the fans were running and the head lights were on the guage would read right on the 13 or a bit below. Now the needle sits on the far right. I don't know how reliable this gauge is but relative to what it was reading before its improved BIG TIME. Another noticable difference was that the car was having a harder time to start after each use indicating battery drain. After running the car 45 mins to and from the drag strip she is starting to crank up faster.

Problems:
the only thing that is bothering me now is that I am not reading 12v across the fans, I am only reading 11.00-11.08 consistant volts. When the car is in regular driving around the nieghbor hood the temp gets REALLY low but once I hit the freeway at 2500rpm the temp stays at 190 or so, before it would be at 180. I think that 1V is making a big difference with the CFM of the fans. Maybe I am worring about it to much but if its suppose to have 12V I am going to try for 12V!! I didn't have time to tinker with grounds and 12V sources, I will hopefully do that this Sunday

Oh yeah just to test how the wires would hold at 6000rpm I raced my bud in his 74 Nova from a roll and by 100mph I had 3-4 cars on him and my wires didn't smoke or melt like the last time.

I will try and provide pics

[Jack]

/akray4play ... the disadvantage of a one wire alternator is lower voltage. the line loss (voltage drop) with external regulator alts actually adds to the total output. most regulators are set for 13.7 to 14.2 volts. regulator sees 13.5 volts, and the battery post sees 14.2 volts (numbers are different for every alt). a one wire alt will only put out the amount of the regulator. a three wire will put out what the regulator is set for plus the line drop to and from the regulator, usually around .5 volts. that extra half volt may be helpfull for your fuel injection.

Frank:
Maybe what ak says about the .5V applies to your drop at fans? Have you also measured fan volts both at idle & 2K?
JACK