i'm glad to have the benefit of walt's knowledge here. i'm sorry bugman had this experience.
just about 4 days ago, i learned from an "old timer" that the chrysler flathead 6 had what he called a "soft crankshaft". this guy apparently had a lot of experience with them as a user. basically, he was saying don't push it. other than that, he didn't have anything bad to say about it.
i don't know if the "issue" was the crank or bearings, but i DO know that dodge later put a forged crank in the 251 power wagons. i would presume that the others are not. seeing as how we're talking about an engine that first went into production in 1933, i can see how my expectations of today might exceed the tolerances of yesteryear.
simply put, 50 miles per hour was a pretty good clip on the lousy roads of 1933. on the other hand, i know the engine is a stout one, given that it continued production into the 1970's in various applications.
jeff, don't give up on it!!! i don't want to lose any true believers. please bear in mind that this is still new to me, and my opinions certainly shouldn't be considered as gospel.