Mahle MS GM 6.6L L5P 4.055in Bore 3.898in Stk 6.417in Rod -41.2cc 15.8 CR w/Thermal Barrier Set of 8

These Mahle cast performance pistons are built for the GM 6.6L Duramax L5P engine, featuring a 4.055-inch bore and a 3.898-inch stroke. The pistons themselves measure 6.417 inches from center to center on the rod journal, with a 1.417-inch pin diameter. This specific design choice, along with the -41.2cc dish volume, contributes to a 15.8:1 compression ratio, which is crucial for efficient diesel combustion. Each piston weighs in at 927 grams and includes a thermal barrier coating (TBC) on the crown, a notable feature that helps reflect heat away from the combustion chamber. This not only aids in managing combustion temperatures but also contributes to improved durability under demanding conditions.

The construction utilizes a cast performance piston design, offering a solid balance of strength and weight for many performance applications. The M174+ designation indicates a specific Mahle material or design standard, ensuring these pistons meet rigorous performance expectations. This set is designed to work with a 403 cubic inch displacement, making it a direct replacement or upgrade for stock L5P engines. It's important to note that these pistons are not CARB approved and cannot be shipped to California due to emissions regulations.

When rebuilding or upgrading your Duramax L5P engine, choosing pistons with the right compression ratio and thermal management is key to achieving reliable performance. This Mahle set provides a well-built option with advanced features like the thermal barrier coating to help protect your engine and optimize its power output. Ensure you consult your engine builder or service manual for specific installation requirements and compatibility with other engine components.