Causes of engine block crack?

Could the end gap have been to tight and broke the ring lands and the top of the piston?

As far as my sons cost Call him and get a price. I was down there today to baby sit his girls with my wife. He was neutral balancing a 360. I gave him all my 340 blocks but I don't know if any are for sale. He is a worse hoarder than I am.

But he does many sleeves in engines of all types.