CAST PISTON COATED

The Federal Mogul H634CP30 is a set of eight hypereutectic pistons designed for various Chevy engine applications. These pistons feature a dome style with two valve reliefs and are constructed from a hypereutectic aluminum alloy containing 16 percent silicon for enhanced strength and wear resistance. They are molded using permanent-mold technology to ensure precise fit and tight bore clearances.

The pistons have a bore size of 4.155 inches (105.537mm) and a stroke of 3.750 inches, with a stock engine stroke type. The rod length is 5.700 inches and the compression height is 1.425 inches, with a piston head volume of -0.20cc. The wrist pin style is press-fit or floating, and the pistons include wrist pins and retainers, with a pin diameter of 0.927 inches. The piston ring thickness is 5/64 in. x 5/64 in. x 3/16 in., and they are not file-fit.