One wire Alternator

[JRouche]

I see a bunch of people saying don't do it?? but why?? just curious?

I dont get it. I changed my system to a one wire alt and dont have ANY issues. I read the MAD info from the link. They didnt talk about much cept that you can have an idiot light. They said the one wire alts weren't readily available from main stream auto parts store, thats BS.



You can use a volt guage or amp guage with a one wire alt just fine. You want a dummy light to tell you when things are bad, yup, you can have that too. I think the link to the MAD site is bad info.

I still dont see ANY real info why a one wire alt is a bad thing. I do see ALOT of good info on why they are used though. JR

[SLO_Z28]

I still dont see ANY real info why a one wire alt is a bad thing. I do see ALOT of good info on why they are used though. JR

reasons they are bad:
Poor output at low RPM's
VERY Poor voltage regulation
Poor availability
More expensive than a simmiler output 3 wire

Reasons they are good:
Easy to install.


Dont be lazy, dont waste your money, get a 3 wire. I ran a Pep Boys that had 475,000-515,000 parts and not one of them was a 1 wire alternator. We had 20-30 CS and SI alternators though.

[Rod]

reasons they are bad:
Poor output at low RPM's
VERY Poor voltage regulation
Poor availability
More expensive than a simmiler output 3 wire

Poor output at low RPM's- 1 wire alts require the RPM to reach 1400 to begin proper charge that's were the ignite switching level on most are set - and once 1400 is reached they continue to charge till ignition is turn off and cycle starts again
VERY Poor voltage regulation- that's usually a poor engine ground, that symptom often doesn't show with a multi wire set up because there is a alternate ground in the 3 multi wires (field wire, stator wire, ground wire)
Poor availability- ?? our local pep boys has them, so does O'rielys, and we carry them from power master in their white box series in chrome for as little as 70 bucks (and that's a chrome name brand?

I'm not for them or against, I just want a reason for the negative opinions?
I saw the same thing about a cylinder head company where everyone bashed them so I had a set sent to the shop and put on my 383, after install I made over 400 plus HP, and have now run them for 3 years at SCCA and autocross events without a problem, there was even a write up in car craft (that the new little company made good cylinder heads), and the guy that bashed the company was a mechanic for 20 some years (so he claimed)

[TBART70]

If you underdrive the pulley it will not charge at idle. The one wire I have charged at 15 volts. A little too high for me, that's why I put the larger puller on it. I want to change it to 3 wire, can I change the regulator?

[H2Ogbodies]

Willy...the 3-wire alt. have regulator that maintain system voltage at all times by "sensing" any drop in voltage by an increase demand in amperage draw via an accessory being turned on. When amperage demand goes up, system voltage goes down. As voltgae increases amperage requirements for any given accessory goes down (to a point). So, you need a regulator that can stabilize the system under all conditions. A 1-wire is RPM based in terms of amperage output. One problem is they can't maintain system voltage when amperage requirements is higher than they can put out @ low RPMs. Say you are getting 60 amps @idle from your 1-wire-but you have the AC on, electric fan running, HO headlights on, stereo blasting, etc. and you are using 60-70 amps. Your alternator will not "put out" any more amperage because it cannot stabilize voltage-instead, voltage proportionately decreases as amperage demands goes up. Now your battery has to act as a buffer...but at the risk of not charging much. For short periods of time, this works-but is not ideal, thus the drawback of a 1-wire on a vehicle that sees a lot of low speed driving with a lot of electrical devices. Most people with 1-wires don't think they have a problem because at leats for a short while the battery buffers the voltage loss. I deal with a lot of electrical issues and I have a solution for you for your exact situation. I have an SI alternator that is 105 amps and is a direct swap for yours and I can explain what you need to do to modify your existing wiring for an internally regulated alt. by simply using the wiring you currently have. Pm me for a diagram...might be easier to walk you thorugh it over the phone-let me know.