Seen a few broken forged cranks, but never a cast one?
My mates 70 R/T Charger was driving around with a totally sheared crank.
It made a strange rattling noise but seemed OK?
I’ve also seen a hemi Barton 572 crank in three pieces too.
That didn’t run too good though...
But some folks do run cast as they is lighter and are not prone to breakage.
Where the limit is, we may never know.
Too many steel cranks around for big blocks, unlike Ford guys...
If you read about the 360 small block guys, they love ‘em lol...
I saw a dropped valve 360 engine that was destroyed and the crank was fine...