ive managed to save 5 items from this block
3 pistons
the lower girdle
and a plug from an oil gallery
new diagnosis
at some point this engine had the chain fail causing damage to #4 piston valve marks and pinched piston ring
im thinking that weakened the piston also
the engine looks to have been thrashed at full throttle with no oil spinning all 4 big end bearings then the they all got hot and one broke then the rest is history
3 pistons
the lower girdle
and a plug from an oil gallery
new diagnosis
at some point this engine had the chain fail causing damage to #4 piston valve marks and pinched piston ring
im thinking that weakened the piston also
the engine looks to have been thrashed at full throttle with no oil spinning all 4 big end bearings then the they all got hot and one broke then the rest is history