I agree on the comments about the fillet/radius in the journal corners - there isn't hardly any to be seen. This creates a heck of a weak spot.
Just for comparison, here is the 4" Merc crank that I just put in my 284 cube 42 Merc engine last year - the crank has been offset ground/stroked to 4 1/8".
Notice the nice radius in the rod journal corners - something that I always have done (have a REALLY good crank grinder here in Ohio).
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