GM LS Piston Set 4.075 Bore -13.4cc

The GM LS Piston Set 4.075 Bore -13.4cc is engineered for serious LS engine builders and performance enthusiasts who demand precision-forged internals for high-RPM applications. Whether you're building a stroker, preparing for forced induction, or maximizing naturally aspirated output, this piston set addresses the core requirement of any reliable engine refresh: controlling combustion chamber volume and maintaining proper compression ratios. These pistons are essential components for anyone undertaking a complete LS bottom-end rebuild or custom engine assembly.

The -13.4cc dish design creates a smaller combustion chamber, allowing builders to achieve desired compression ratios without additional block modifications or the need for thinner head gaskets. This geometry is critical for tuning power output across both naturally aspirated and boosted platforms, where chamber volume directly influences ignition timing, fuel requirements, and peak pressure characteristics. The 4.075-inch bore specification matches modern LS variants and popular stroker combinations, ensuring proper wall thickness and ring seal integrity. Forged construction provides the strength necessary for sustained high-boost applications, high-RPM sustained operation, and the thermal cycling demands of performance driving.

LS platform builders—whether developing drag, road race, or street performance engines—rely on piston sets like this for bottom-end durability and tuning flexibility. The -13.4cc dish is particularly suited to LS2, LS3, and stroker builds where increasing displacement or adding supercharger/turbo systems demands careful compression management. Installation requires precise piston ring fitment, correct rod bolt torque specifications, and proper deck clearance verification; work with an experienced machine shop if this is your first engine build. This piston set pairs seamlessly with quality connecting rods, premium oil systems, and modern fuel management to deliver reliable, repeatable performance gains.