There is a difference in cast crankshafts, though. The stronger ones are nodular iron. Standard cast iron crankshafts are ok, but they are not as strong as nodular iron. I always use the 351 Cleveland as an example. They never had a steel crankshaft option, but they were equipped with the nodular iron heavy duty crankshaft. Those engines routinely saw 9000 plus RPM on NASCAR and NHRA circuits, just as the 360 Mopar crankshafts. That's why I never thought it was a big deal which crankshaft was in a Mopar, because they are all good. But some people just throw them in the ditch because they ain't forged.