"The interesting observation is that these alternators really aren't that efficient -- approaching 50%."

That's because you used the incorrect data!

The data in the Carrera computation is correct -- 92A, .082ohms, 64% efficiency, yes?

-Juan

"Try .01 to .02 ohms."

That is what peaked my curiosity, it didn't seem right.

That and my original alternator is sitting by my workbench where it has me stumped. It draws 100 mA with the key off (of course it quit doing that 10 minutes after I started fooling with it). I thought maybe an in depth study of coil resistance/hy-pot would yield a breakthrough, it did not. Oh yes and I measured reverse leakage of the 11 (2 unused) diodes with 90 volts.