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I keep thinking back to worst case scenario if something should go wrong. Case in point O_D's encounter with the shorted lighter. As he described it, the generator was squealing and the ammeter was pegged. On a generator regulated at 30 amps we can assume that was probably the max output. O_D's car suffered no damage.

What would an alternator capable of 65 or more amps do in that situation? There's a couple of circuits with absolutely no fuse protection so if something happened in one of those the wire would take it all. If anything, a fuse at the alternator would be a better solution than doing nothing else. I believe a lot of modern cars do that very thing with a master fuse or fuse link before the fusebox.

On my car, I have the battery, and alternator tied together at the starter solenoid battery lug. Then there is a 10 gauge with that extends from that lug to the where the original voltage regulator can sits. The inside of that can was gutted and a 50amp master fuse was hidden inside of it. So there is no fuse between the battery and the alternator or battery and the starter. But there is a fuse between alt/bat/starter circuit and the rest of the vehicle harness.

Quote:
"Case in point O_D's encounter with the shorted lighter. As he described it, the generator was squealing and the ammeter was pegged."

If the generator (or an alternator) was not or could not supply enuf current to peg the ammeter then the battery WOULD have.

Or to put it another way:
Suppose the car had absolutely NO gen or alt on it at all. THe cig lighter shorts, then the shorted cig lighter it will draw current from ANY where it can get it. It will get it from the batery in this case.

I belive Kevins design as he describes in post #22 above is the best way to do it. Slick idea.

Kevin. Are u running the ONE wire alt or the 3hree wire alt????

Kevins set up with a fuse in the gutted Voltage regulator can, i assume was done because of convenient location of the VR can which means ez fuse replacement if necessary. Slick idea.

However, if i read my 56 manual right then the OEM set up allows the battery to feed the 'rest of the car' directly from the starter hot post that the battery cable connects to. So kevin must have had to run 2wo wires. One across engine compartment from starter to fuse in dummy VR can and another wire from the fuse back across engine compartment to the original OEM wire that fed the 'rest of the car'.

If the 50 amp fuse blows then head lights and ignition stop??????

Keith, the battery connect to the starter lug through the normal battery cable. The ALT feed from from the Alt, along the fender, and then to the starter lug as part of the normal harness run. There is then a 10 ga feed that runs from the starter lug up to the VR can. Then intenally it run across the master fuse and out the other side of the VR can. Then it goes inside the car to main fuse box under the dash. From there is goes through all the various fused circuits. So yes, if the master fuse blows, headlight, ignition, horn, everything goes dead.

I am running a 3 wire ALT and the current sensing wire is tied to the fuse side of the VR can output. The one turn on wire runs though the GEN idiot light and is tied to the Ignition ON.

Here is a pic of the wire-harness with the VR Can cover removed. I am using the original terminals on the VR.

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AS a side note, we need to all keep in mind that ANY gen or alt output is solely dependent upon the SPEED at which the gen or alt is turning.

So in the case of a 100 or even 50 amp alt we need to know at what SPEED (RPM) the alternator MUST turn in order to achieve 100 amps or it's max amp rating.

So assuming a dead battery and a 100 amp alt then just maybe at 80 to 90 mph there could be problems with the higher amperage because the alt is trying real hard to charge the battery.

Otherwise at reasonable lower speeds of say 30 to 40 mph then the alt would not be able to genenrate enuf current to harm anything.

Bottom line:
We probably need an rpm/amp chart for the alternator conversions before we can make the best final decisions.

You miss my concern on the wire. What I'm concerned about is that approx 7 or 8 feet of original ga wire inside the loom between the alternator/regulator location and any main battery take off point. If something loads heavily or shorts, yes the battery is going to put out but it is also going to be calling for help from the alternator or generator. If the alternator starts putting out max capacity that high amperage thru the original wire to get to the battery is not going to just sit there.