Alternator seized... or something...

I used to blow these things up "real regular." The original setup on my 440-6 '70 RR had a very small pulley, and I figured one time "if I remember" the crank to pulley ration was around 4:1. This means if you spin the engine up to 5 or 6K the alternator is making 20--24000 RPM. The stator would "vibrate" little notches in the alternator case halves where the "nubbins" located the stator in the cases. They would then "sit" crooked and actually rub the rotor/ stator. The windings would vibrate loose, and wear the insulation off between turns where they crossed. You could lift the hood at night, rev the engine, and see a really interesting little "light show." All sparkly and stuff