Question; Will a Gm 1 wire be adequate for an Av8 roadster? I will only have headlights, turn signals, and stereo. I bought one and was advertised as a 40 amp. I did some research and could not find anyone making that type. Thanks
Converting your lights to LED would help lighten the load if that is an option for you. Sent from my SM-N950U using The H.A.M.B. mobile app
40 amp alternators are listed for racing applications. Although in a basic car without a heater you might ony get into trouble at night with the headlights on with extended idling. If you can trade it for even a 65 amp it would give you more cushion.
12si 1 wire can be up to 105 amp in OEM form . That should be plenty to let the Genie out of the bottle if you have a short circuit .
Cars ran generators for years that only put out 3o amps. They had headlights, heaters, and electric seats and windows. So you should fine.
GM 1 wire alternators are street rod parts. This is a traditional hot rod site. BJR is correct !!! Generators were around for a long time and did the job very well.
Your life has changed a bit through the years also , do you heat with coal or wood , light with a candle or coal oil , farm with a horse , use the out house ? All is well , I’m sorry , it’s sad when someone asks we help and we are called out for just p***ing on HELP ! Again I’m sorry , I should have known better .
"One wire" is a sign of wanting the easy way out..., or better definition yet, "lacking confidence in wiring a 3 wire one" ..... no offence, but usually true.. I have three vehicles I use as primary cars... I own nothing newer than 48 years old!...TWO are generators, one of these 2 runs factory EFI! It puts out 14.2v at IDLE, but most won't believe that here. the only alternator one is 35-37A factory with factory A/C, a 1966 K20 truck Why be sorry for being correct, without really knowing it, when you said "105 amps is enough to let the genie out"? << I originally "took" your sentence as "105 Amps feeding a dead short on the positive battery cable if a problem like from chafing!" Also, 105 alternator would need a heavy duty drive belt system if the car was jump started with a dead battery...that output would also need m***ive wiring in that very rare, odd situation. GM last ran a "single" V belt on the old first gen 80 A in the 1980s, and that V belt with those loads, actually wore out the sides of the V pulleys in just "normal" use! That is why serpentine, "multi V-grooved" flat belts were eventually needed. ps, sitting by my wood stove right now no chit.. lol
Depending on your ignition system you might mav have trouble shutting the engine 'Off' with a 1 wire alt. That 'gen' light in the dash is what actually shuts the engine 'Off' when you turn the key, that light is in series with the Altenator field and shorts it out killing the altenator and power to the engine. With a 1 wire altenator the field is internal and self generating, you can turn the ignition key to 'Off' after the engine is started without any effect to the altenator. You might have to add a diode to the alt circuit or a seperate ignition switch. Like I say, it all depends on the ignitioin system, just have a way to disconnect the alt the first time you start it after going to 1 wire.
A 10si will back feed the ignition but a one wire converson won't no wiring going to the ignition system. I worked on cars in the generator era and the alternator was a great improvement. If someone didn't reverse polarity installing the battery or jumper cables not much ever went wrong.
I run the 3 wire as 20 years ago any ford junker in any backyard had one... sad to say today it is the one wire doar car that is behind the shed... buddy says you need an idiot light to run a one wire...?
Most of them are 65 amp alternators. But even a 40 amp should feed your roadster unless you built the stereo like a stereo inn a ghetto cruiser. You don't run into big amp requirements until you start running things like high watt headlamps and killer stereos electric windows and locks and the like. On an A V8 you shouldn't have many electrical requirements unless you have built one helluva stereo system.
A 3-wire can be easily changed to a 1-wire by hooking its 2nd spade voltage sensing terminal to main output with a small thin wire. Or it can just as easily be changed to a 2-wire by also hooking its 1st spade to the ignition switch thru an idiot bulb. Or it can be done right as a 3-wire by simply hooking the 2nd spade to some remote hotspot with a longer thin wire. Jack E/NJ Hey BB! That doesn't look like a traditional GM 1-wire! 8^)
Couldn't agree more View attachment 3883047 100 amp one wire power gen. [/QUOTE] I agree. Also a 1 wire Power Gen on my flathead. I guess I'm one of the lazy ones.
A 40 Amp alternator should be fine for your stated electrical items. I'm surprised the traditional police haven't jumped on ^^this^^ like a chicken on a June bug.
I'm also a neat freak, especially when there are no hood sides. No external reg, no extra wires, no external solenoid, no ballast resistor, no visible timing box or spark amplifier...keep it looking simple, even when it's not. That's traditional too.
Thank you all for the info. The alternator does have a plastic plug covering up the 2 male spades. Can this be used to convert to a three wire? I was only going for the neatness using a 1 wire. I forgot to mention that I will have an electric fan for the radiator.
That really changes the debate to stay with a low amp generator. Some fans pull a lot...and depending on so many variables in a flathead Ford car build, the 12v fan might, or might not run too much for the generator system.. the Alt could be your best bet, now that we know..
>>>plastic plug covering up the 2 male spades. Can this be used to convert to a three wire?>>> Probably 2-wire since the right voltage sensing spade is internally hooked to output already. The left exciter spade can be hooked up to ignition switch thru a 1-2A idiot light. This 2-wire hookup avoids having to rev the engine that 1-wire hookups sometimes need to start charging. Jack E/NJ
One wires great, you can put a self exciter in any amp I'm pretty sure, napa used to sell em for 7 bucks
If exciter amps too high (eg resistance too low), self running is possibility after ign switch turned off. A diode would then be needed. Maybe that's in the NAPA kit? Jack E/NJ
when i was a kid we drove around all night in 60's vintage chevys with lights on, the heater going full blast, led zeppelin going full blast, dome lite to find the dope, and the car still started at 20 below zero the next day on 40 amp alternators
I do find it hard to believe that everyone seems to be overlooking the fact that this is a traditional hot rod site. Every one of you are correct about how wonderful the one wire whatever will be but that does not change the fact that it is WRONG on a traditional hot rod......period....................and for the powergen crowd..............they are great but not traditional. They are sort of like a blow up doll............kind of look like it and will do the job but it just aint right !!
I usually have a one wire or two on the shelf. That said I am actually going back to a externally regulated GM alternator. That would be alight wouldn't it?
******, you have been here a lot longer than me...............You would have to ask that of @Ryan...........his site, his rules...........
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