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Manley 11673-8 - Chevy LS-1, LS-2 Small Block 1.550 Pro Flo Severe Duty Exhaust Valves (Set of 8)

Manley 11673-8 - Chevy LS-1, LS-2 Small Block 1.550 Pro Flo Severe Duty Exhaust Valves (Set of 8)

Manley | 11673-8
SKU: BBPB-11673-8
Regular price $310.99 USD
Regular price $401.42 USD Sale price $310.99 USD
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Manley 11673-8 - Chevy LS-1, LS-2 Small Block 1.550 Pro Flo Severe Duty Exhaust Valves (Set of 8)

Exhaust Valve - 1.550 in Head - 0.3136 in Valve Stem - 4.923 in Long - Stainless - GM LS-Series - Set of 8

Head Diameter: 1.550 in. - Stem Diameter: .3136 in. - O/A : 4.923

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.

  • 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
Product Market: Domestic
Head Diameter: 1.550
Valve Head Diameter: 1.550
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
Tip Length: 0.175
Margin Width: 0.065
Seat Width: 0.115
Top of Head: 18 Degree Dish
Valve Head Shape: 18 Degree Dish
Underhead Angle: 25.00
Underhead Radius: 7/16
Weight: 88
Cylinder Head: LS6 Cylinder Head
Valve Series: Severe Duty? Series
Valve Material: Stainless Steel
Valve Type: Exhaust
Product Type: Engine Exhaust Valve Kit
Valve Quantity: 8
Engine Valve Quantity: 8
Industry: Automotive
Out of Stock Message: Call for Availability
Engine Type: ICE
Make: Chevrolet
Engine: LS1
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