Manley Severe Duty® Valves deliver the ultimate in strength, reliability, and high-performance durability. Engineered for extreme gasoline engine temperatures, these valves are crafted from exclusive materials (XH-428 for exhaust and NK-844 for intake), offering unmatched tensile strength compared to competitive alloys. In fatigue testing at 40,000 psi and 1400°F, Manley exhaust valves endured 100 million cycles, while competitors failed after just 100,000, proving a 1,000× longer fatigue life. Each valve features chrome stems, hard tips, and swirl-polished underheads with fully machined combustion faces for superior airflow, efficiency, and wear resistance. Built for those who demand race-winning strength and precision, Manley Severe Duty® Valves set the industry standard for performance and endurance.
Manley Chevy LS-6 Head Small Block Severe Duty/Pro Flo Exhaust Valves (Set of 8)
Severe Dty. Ex. Vlv Kit - Chevrolet Gen III/IV Small Block - LS1, LS2, LS8
Swirl polishing and machined faces improved airflow/optimized efficiency
Exotic alloys for superior tensile strength, reliability, and longevity
Head Diameter: 1.600 in. - Stem Diameter: .3136 in. - O/A : 4.923
Proven fatigue strength for extreme performance
Chrome stems and hard tips enhance durability
Manley Valve - Exhaust, Valve-LS1 S/D 1.600.
Manley Valve - Exhaust, Valve-LS1 S/D 1.600
Engine Exhaust Valve
Valve-LS1 S/D 1.600
Valve - Exhaust
