SBC Dished Piston Set 4.030 Bore -18.9cc

The SBC Dished Piston Set 4.030 Bore -18.9cc by Race Tec Pistons is a purpose-built forged piston kit engineered for small block Chevrolet engines requiring high-performance compression geometry and reliability. This eight-piece piston set is designed for builders and enthusiasts who demand precise bore sizing and controlled compression ratios in naturally aspirated or moderately boosted applications. The dished crown design reduces peak pressure and combustion chamber volume, making these pistons ideal for street engines, mild-to-moderate performance builds, and applications where detonation control is critical.

Each piston in this set features Race Tec's forged construction, delivering superior strength and thermal stability compared to cast alternatives. The 4.030-inch bore diameter accommodates typical small block Chevy overbore specifications, while the -18.9 cubic centimeter dished cavity actively reduces combustion chamber volume to achieve lower compression ratios—a critical feature for pump-fuel engines running standard octane fuel or those prone to knock. The ring groove configuration (1.5 x 1.5 x 3.0 mm) is optimized for standard small block Chevy ring packages, ensuring proper ring seating, blow-by control, and long-term durability. Forged construction provides exceptional fatigue resistance under sustained RPM loads and thermal cycling.

This piston set is ideal for small block Chevy engine builders targeting street performance, bracket racing, or vintage hot rod applications where factory-style reliability and control are priorities. The dished geometry is particularly suited to engines running pump gasoline (87–91 octane) without sacrificing performance or requiring premium fuel. Installation requires precision honing to the specified 4.030-inch bore diameter and proper ring end-gap verification. The complete eight-piece set ensures matched compression and consistent performance across all eight cylinders, critical for engine balance and longevity. Verify piston pin diameter and connecting rod compatibility before final assembly.