the head bolt would have to be a foot long and it still would not crack in the valley they would just bottom out .the thinner 350 blocks crack there i have seen more then one . as for the rest of the mess you have if the caps were not tang to tang it very well would not turn over .i would bet it was not clean when put to gether so that will screw stuff up .it just sounds like someone did not know what they were doing or did not care