Hypereutectic Piston Set, 4.040 Inch Bore

The Keith Black KB198-040 piston set is engineered for Small Block Chevy Gen I engines, specifically designed for a 4.040-inch bore. These pistons are constructed from hypereutectic aluminum, providing a balance of strength and lighter weight compared to cast pistons. Key specifications include a 1.561-inch compression height, a 0.927-inch pin diameter, and a piston head volume of +6.25cc. The pistons feature 4 symmetrical valve reliefs and a centered pin design. They also come with Triple Spiral Lock Rings and have CNC machined pin bores for precision. Additional features highlighted in the product information include a coated skirt for improved oil control and reduced friction, as well as fully machined heads and valve reliefs for enhanced performance. The wrist pin style is compatible with both press-fit and floating configurations.