{"product_id":"manley-chevy-small-block-ls3-l99-l92-head-1-6in-head-dia-severe-duty-exhaust-valves-set-of-8","title":"Manley Chevy Small Block LS3\/L99 (L92 Head) 1.6in Head Dia. Severe Duty Exhaust Valves (Set of 8)","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":47839846334690,"sku":"MAN12355-8","price":452.49,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0748\/5004\/2082\/files\/fec5f7dba71aff461c53f7b003c4211fL_610ea42b-94ad-4f76-8a73-e6d4152431f1.jpg?v=1780097707","url":"https:\/\/raceclub.us\/products\/manley-chevy-small-block-ls3-l99-l92-head-1-6in-head-dia-severe-duty-exhaust-valves-set-of-8","provider":"Race Club ","version":"1.0","type":"link"}