Crankshaft hardening machine - GIF

[madokie]

Cast Iron crankshafts were turn into NI ,(Nodular Iron) cranks by heat treating, back in the day 1964-1974 ,by Generous Motors, i wonder if they did it this way, or put a big load in a giant oven.??us Pontiac V8 guys are always on the lookout for crankshafts with the N cast on a counter weight, for our motors, they are really strong crankshafts..