Wow !! A blast from the past as I believe that's one of mine. I converted Sach 4.2's primarily for B & B who sold most of them for me. They were a great engine with plenty of power and durability and I built over a 100 of them. The majority of engines built since then with machined cases used the Sachs cranks, rods, pistons and cylinders until recently as we're now seeing different and cheaper internals showing up.