This sort of thing has been going on for a long time. Back when I thought I was a restorer I bought a Model A engine and found it had a piece cracked out of the outer water jacket. When I took the head off I realized it probably had been through a home-rebuild and one of the pistons was put in backward. Since the pins were offset in the pistons to reduce "slap", the backward piston must have really led to vibration/slap and probably caused the crack in the block and that probably was due to some home mechanic back in the 1930s. Once I had a rod poke a hole in the side of my "Blue Flame 235" in a '54 Chebbie on an Interstate. I stopped the car, lifted the hood, saw the rod oscillating in and out of the side of the block and drove another ten miles home on five cylinders. Cast iron is hard but brittle!

Don Shillady
Retired Scientist/teen rodder