CP Pistons GM Duramax 6.6L 4.075 Bore 3.8976 Stk 6.418 Rod 1.946 CH -38.5cc Dome Pistons (Set of 8)

This set includes eight forged pistons from CP Pistons, specifically made for GM Duramax 6.6L engines. These pistons feature a 4.075 inch bore, designed to work with a stock 3.8976 inch stroke and a 6.418 inch rod length. The compression height is 1.946 inches, and each piston has a -38.5cc dome, which will affect your engine's compression ratio.

CP Pistons are well-known for their robust construction, and these are no exception. They are forged from high-strength aluminum alloy, a common choice for performance and heavy-duty applications because it offers a good balance of strength and weight. The forged process creates a denser, stronger grain structure compared to cast pistons, making them more resistant to the extreme pressures and temperatures found in a modified or high-performance diesel engine. The -38.5cc dome shape is carefully calculated to work with specific cylinder head volumes and gasket thicknesses to achieve a target compression ratio, often for boosted applications where controlling detonation is key.

When installing these pistons, it's important to follow the manufacturer's detailed specifications for ring gap, bearing clearance, and piston-to-wall clearance. These are critical for engine longevity and performance, especially with the increased cylinder pressures that these pistons are built to handle. This set is intended for builders looking to upgrade or rebuild their Duramax engine for increased power or durability.