Will this 15V voltage regulator "work" on my ‘56 Ford Fairlane car, 292, automatic, no air, all manual with an original generator? Or does it have to be a 12v instead of the 15v?
I would lean towards this being correct for the era. I’ve seen them marked like this, always figured it meant the current cut out @ 15 volts.
That part no. FAP-10505-B is regulator for 1956 Thunderbird If you look at regulators here https://www.macsautoparts.com/ford_thunderbird/engine-and-related/ignition/regulators.html you'll see that the ones stamped with original style lettering say 15V. You can even buy a repro decal Use it.
It's got screws to take the lid off, so unless it's a reproduction solid state unit, it should be mechanical with an adjustment I would think. The old mechanical units could be adjusted up or down with a screw on the points arm. I've turned them up when I had one that didn't keep the battery quite charged enough. 15 volts is probably max, it's probably set to 12.5 or 13 volts.