Bob DeWachter and his friend Dave Perreault have been hard at work on 470’s stoker. With the cylinder bores newly machined .0625” oversized, new cast iron pistons had to be made to properly fit the new bores.

The original pistons were machined castings. The new pistons were machined from pieces of G2 cast iron using a lathe and a CNC milling machine to make the piston cavities front and back. Check out the story in the photo captions below!