Manley Chevy LS-6 Head Small Block Severe Duty/Pro Flo Exhaust Valves (Set of 8) - 11677-8

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.

Features

• Proven fatigue strength for extreme performance
• Chrome stems and hard tips enhance durability
• Exotic alloys for superior tensile strength, reliability, and longevity
• Swirl polishing and machined faces improved airflow/optimized efficiency

Specs

• Head Diameter: 1.600 in
• Stem Diameter: .3136 in
• O/A : 4.923
• Manley Valve
• Exhaust, Valve-LS1 S/D 1.600
• Out of Stock Message: Call for Availability
• Title: Manley Valve - Exhaust, Valve-LS1 S/D 1.600
• Prop 65 Yes/No: Yes
• Prop 65 (C, R or CR): CR
• Industry: Automotive
• Engine Valve Quantity: 8
• Valve Quantity: 8
• Prop 65 - Short Label: Prop 65 Warning Label.JPG
• Engine Type: ICE
• Make: Chevrolet
• Engine: LS1
• Product Market: Domestic
• Head Diameter: 1.600
• Valve Head Diameter: 1.600
• Stem Diameter: 0.3136
• Valve Stem Diameter: 0.3136
• O/A Length: 4.923
• Installed Height: Stock
• Valve Length: 4.923
• Valve Tip Length: 0.175