BBC Domed Piston Set 4.500 Bore +36cc

The Sportsman Racing Products BBC Domed Piston Set 4.500 Bore +36cc is a forged high-compression piston assembly engineered for big-block Chevy marine and performance engines requiring elevated combustion chamber volume. This set of eight pistons is purpose-built for boaters and engine builders seeking increased displacement and compression dynamics in severe-duty marine applications, from tournament fishing rigs to offshore speedboats where sustained high-rpm performance is non-negotiable.

Each piston features a domed crown geometry that adds 36 cubic centimeters of combustion chamber volume per piston—a significant specification that directly impacts fuel mixture atomization and burn characteristics in big-block applications. The 4.500-inch bore diameter represents the upper tolerance range for BBC engine blocks, accommodating serious overbore machine work. Ring groove configuration (1/16 x 1/16 x 3/16 inch) is optimized for conventional compression and oil control rings, supporting both naturally aspirated and supercharged engine builds. Forged construction provides the material strength necessary to withstand repeated detonation cycles and the thermal cycling inherent in high-output marine duty where water-cooled blocks operate under sustained load.

This piston set is specified for marine engine builders, tournament anglers running heavily modified big-block powerheads, and experienced shops performing custom BBC rebuilds. The +36cc dome is particularly relevant in applications where factory displacement has been maximized through overbore and stroke combinations, requiring matched compression geometry to maintain optimal power delivery across the rpm band. Proper installation requires precision honing, ring seating, and dynamic balancing as part of a complete engine assembly process—not a bolt-in maintenance item.