Fleece Performance billet rocker arm bridges for the GM Duramax. These bridges offer a massive 2.5-time strength improvement over factory bridges. Machined from billet 8620 steel, the bridges are surface ground for flatness, feature improved oiling to the valve stems, and case hardened and...

Introducing our Freedom Series cylinder heads for the 6.6L Duramax! Each cylinder head is manufactured in our state-of-the-art Freedom Racing Engine shop and is guaranteed to meet or exceed factory specifications. All heads are meticulously inspected, pressure and leak tested, and are equipped with...

Introducing our Freedom Series cylinder heads for the 6.6L Duramax! Each cylinder head is manufactured in our state-of-the-art Freedom Racing Engine shop and is guaranteed to meet or exceed factory specifications. All heads are meticulously inspected, pressure and leak tested, and are equipped with...

Upgraded 7/16 inch diameter pushrods for GM's Duramax 6.6L diesel engines. Produced from 4130 chrome molybdenum steel and heat treated to Rockwell Rc60 for outstanding strength and rigidity. These pushrods are designed to stand up to higher valve spring pressure, RPM, and cylinder pressure...