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I think it was loose but they ran it anyway it is also on a cheby 383.
He was told the tci rattler ruined the crank because they are crap and the weights try to turn the crank when you shut it down.



That could very well be the issue. Crank mfgs see a lot of problems with Chevy SB cranks breaking at the nose. It is usually due to specific brands of dampers. Mopar cranks are quite a bit stronger on the nose and so they don't have as many issues but the SBC cranks are prone to failure if they don't have a good damper.