CHEVY 400 MAIN 2PC REAR SEAL COMPETITION SUPERLIGHT ROTATING ASSEMBLY UNBALANCED

This rotating assembly from Scat (MPN: 1-40578) is designed for custom-built Chevy Small Block 377 engines, which are derived from a 400 small block with a 3.750" stroke. It is specifically compatible with engines requiring a 2-piece rear main seal, typically found in Chevrolet models prior to 1986. The assembly includes a 4340 forged superlight crankshaft, Ultra Q-Lite H-Beam connecting rods, Mahle premium pistons, rings, and rod & main bearings. It is an unbalanced assembly, requiring internal balancing for installation. The crankshaft features a 3.500" stroke and 400 main bearing size. Piston compression ratios can vary with cylinder head volumes (e.g., 11.5:1 with 58cc heads, 10.7:1 with 64cc heads, and 10.0:1 with 72cc heads).