Pacific Performance Engineering LB7 Cast Iron Cylinder Heads

OEM Duramax cast aluminum cylinder heads fall short over time; the different heat expansion crates between cast iron engine block and cast aluminum cylinder head cause head gasket scrubbing, and eventually blown head gaskets. Aluminum cylinder heads are also prone to warping, melting, and/or cracking in high performance applications where excessive heat is introduced. Pacific Performance Engineering LB7 cast iron cylinder heads are the ultimate upgrade to your Duramax engine and eliminate any head gasket or cracking concerns. Cast from high-quality alloyed grey iron, PPE LB7 cylinder heads offer elevated fatigue strength and heat and creep resistance, which prolongs the cylinder head's lifespan significantly. They also share the same heat expansion rate as the stock cast iron cylinder block, so no more blown head gaskets. These cylinder heads also feature cast-in fuel injector cups and solve the OEM injector cup leaking issue. Each head comes complete with brand new springs, spring retainers, spring locators, valves, valve seals, valve keepers, valve seats, valve guides, rocker arm dowels, and freeze plugs. Whether you have a damaged aluminum cylinder head or a desire for better reliability and longevity on your Duramax engine, the Pacific Performance Engineering LB7 cast iron cylinder head is undoubtedly the best choice. Component features and benefits: * Premium 21-4N, Stellite-reinforced exhaust valves, and chrome-silicon alloy intake valves * All valves are fully nitridated with increased abrasion resistance * High-strength, CNC-machined chromoly steel spring retainers and spring locators * Upgraded tapered valve springs provide faster response and eliminate valve float at high rpms * Powdered metal valve seats offer superior wear and heat resistance * Significantly reduced diesel engine clatter compared to the factory aluminum cylinder heads * Increased thermal efficiency compared to aluminum heads * 3-Year Unlimited Mileage Warranty Show Less