Performance Piston Set

These KB Performance hypereutectic pistons, part number KB422.030, are designed for Pontiac 400ci engines from 1967 and later. They are engineered to work with 14-degree heads and feature a solid dome top with 10.0cc and two valve reliefs. The piston sits 0.025" below a 10.250" deck height. Before assembly, ensure a minimum of 0.045" clearance per side between the small end of the connecting rod and the piston. Key specifications include a 4.150" bore, 3.750" crankshaft stroke, and 6.630" connecting rod length. The compression height is 1.710", and the pin size is 0.980" x 3.000", with the pin located in the center. It has a top landing height of 0.300" and ring grooves of 5/64" top, 5/64" middle, and 3/16" bottom. These pistons offer a 9.4:1 compression ratio with 100cc combustion chamber heads. The kit includes information on piston ring end gap for hypereutectic pistons. The product is also discussed in various online videos regarding engine building and the differences between piston types.