50 States Emissions Legal (E.O. D-701-38) The OEM Duramax cast-aluminum cylinder heads fall short over time - the different heat expansion rates between cast-iron engine block and cast-aluminum cylinder head cause head gasket scrubbing and eventually blown head gaskets. The aluminum cylinder heads are also prone to warping, melting, and/or cracking in high-performance applications where excessive heat is introduced.

PPE's new LB7 Cast Iron Cylinder Head is the ultimate upgrade to your Duramax engine and eliminates any head gasket or cracking concerns. Cast from high-quality alloyed gray iron, the PPE Cylinder Head offers elevated fatigue strength, and heat and creep resistance, which prolongs the cylinder head's lifespan significantly.

PPE Cylinder Heads also share the same heat expansion rate as the stock cast-iron cylinder block no more blown head gaskets. PPE LB7 Cylinder Heads also feature cast-in fuel injector cups and solve the OEM injector cup leaking issue.

Each head comes complete with upgraded valve train components. All valves are made of superior materials and fully nitridated. The tapered valve springs' higher spring rate and lighter retainers/locators enable faster response during higher RPMs and eliminate valve float. Powder metal valve seats provide superior wear and heat resistance. The denser and stiffer material properties from the cast-iron construction also significantly reduce engine clatter.

Whether you have a damaged aluminum cylinder head or a desire for better reliability and longevity on your Duramax engine, the PPE Cast Iron Cylinder Head is undoubtedly the best choice.

Duramax Iron Heads Upgrade: Diesel World

Unboxing PPEs new Duramax cylinder heads!: LinCo Diesel Performance