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
- Manley Valve
- Exhaust, Valve-S/D 1.600,+100
- Exhaust, Valve-S/D 1.600,+.100
- Product Market: Domestic
- Head Diameter: 1.600
- Valve Head Diameter: 1.600
- Stem Diameter: 0.311
- Valve Stem Diameter: 0.311
- O/A Length: 5.040
- Valve Length: 5.040
- Valve Tip Length: 0.290
- Tip Length: 0.290
- Margin Width: 0.080
- Seat Width: 0.100
- Top of Head: 9 Degree Dish
- Valve Head Shape: 9 Degree Dish
- Underhead Angle: 15.00
- Underhead Radius: 1/2
- Product Type: Engine Exhaust Valve Kit
- Valve Quantity: 8
- Engine Valve Quantity: 8
- Industry: Automotive
- Valve Type: Exhaust
- Valve Material: Stainless Steel
- Valve Series: Severe Duty? Series
