{"product_id":"manley-chevy-big-block-chevy-1-880in-severe-duty-exhaust-valves","title":"Manley Chevy Big Block Chevy 1.880in Severe Duty Exhaust Valves","description":"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.","brand":"Manley Performance","offers":[{"title":"Default Title","offer_id":51291317403950,"sku":"MAN12843-8","price":344.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0672\/0779\/0894\/files\/48848c00e871784319a2f846e181c633_83268e69-b20f-4118-b89c-789abe3c3d47.jpg?v=1763511791","url":"https:\/\/muscleandtrucks.com\/products\/manley-chevy-big-block-chevy-1-880in-severe-duty-exhaust-valves","provider":"Muscle \u0026 Trucks","version":"1.0","type":"link"}