{"product_id":"head-diameter-1-600-in-stem-diameter-3136-in-o-a-4-927","title":"Manley 11677-8 Head Diameter: 1.600 in. - Stem Diameter: .3136 in. - O\/A : 4.923","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","offers":[{"title":"Default Title","offer_id":51244621365563,"sku":"BBPB_11677-8","price":625.06,"currency_code":"CAD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0955\/5958\/2011\/files\/public_86e47483-8090-4955-8ea6-702dc566931c.jpg?v=1778482197","url":"https:\/\/performancepartscanada.ca\/products\/head-diameter-1-600-in-stem-diameter-3136-in-o-a-4-927","provider":"Performance Parts Canada","version":"1.0","type":"link"}