Well for the most part the engine was Veco. The piston was meehanite and the cylinder was leaded steel. These were removed and the after market chromed sleeve and the 7075 T6 piston with dykes ring were installed. There was also the McCoy rod replacing the original rod. This had phospher bronze bushings in both ends. The piston and sleeve were a larger bore than the original giving the engine a displacement of .21/3.5cc. The McCoy head was also a nice unit with a squish band of .075 wide. It was a bloody shame the head contour was interrupted by the slot milled to clear the piston baffle.