{"product_id":"manley-chevrolet-big-block-exhaust-valve-kit-1940in-head-dia-5422in-oa-length-03110in-stem-879499-t14","title":"Manley Chevrolet Big Block Exhaust Valve Kit - 1.940in Head Dia. 5.422in O\/A Length, 0.3110in Stem","description":"\u003ch3\u003e\u003cstrong\u003eManufacturer Part # : 12803-8\u003c\/strong\u003e\u003c\/h3\u003e\u003cbr\u003e\u003ch2\u003eMarket Description\u003c\/h2\u003e\n\u003cp\u003eManley 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.\u003c\/p\u003e\n\n\u003ch2\u003eProduct Description - Short\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003eManley Chevrolet Big Block Exhaust Valve Kit - 1.940in Head Dia. 5.422in O\/A Length, 0.3110in Stem\u003c\/li\u003e\n  \u003cli\u003eValve - Exhaust\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eLabel Description\u003c\/h2\u003e\n\u003cp\u003eSevere Dty BBC Ex. Vlv Kit - 1.940 in. Head Dia.,5.422 in. O\/A ,.3110 in. Stem\u003c\/p\u003e\n\n\u003ch2\u003eFeatures and Benefits\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003eSwirl polishing and machined faces improved airflow\/optimized efficiency\u003c\/li\u003e\n  \u003cli\u003eExotic alloys for superior tensile strength, reliability, and longevity\u003c\/li\u003e\n  \u003cli\u003eProven fatigue strength for extreme performance\u003c\/li\u003e\n  \u003cli\u003eChrome stems and hard tips enhance durability\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eAssociated Comments\u003c\/h2\u003e\n\u003cp\u003eManley Valve - Exhaust, Valve-BBC S\/D 1.940.\u003c\/p\u003e\n\n\u003ch2\u003eProduct Description - Long\u003c\/h2\u003e\n\u003cp\u003eManley Valve - Exhaust, Valve-BBC S\/D 1.940\u003c\/p\u003e\n\n\u003ch2\u003eAAIA Part Type Description\u003c\/h2\u003e\n\u003cp\u003eEngine Exhaust Valve\u003c\/p\u003e\n\n\u003ch2\u003eProduct Description - Invoice\u003c\/h2\u003e\n\u003cp\u003eValve-BBC S\/D 1.940\u003c\/p\u003e","brand":"Manley Performance","offers":[{"title":"Default Title","offer_id":47190601302154,"sku":"T14.879499","price":301.07,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0688\/4599\/4122\/files\/639c017773af16048d25285e221903acL_6e47b7c4-9d60-4653-b147-e50d9e4a308b.jpg?v=1760724387","url":"https:\/\/www.sbxperformance.com\/products\/manley-chevrolet-big-block-exhaust-valve-kit-1940in-head-dia-5422in-oa-length-03110in-stem-879499-t14","provider":"SBX Performance","version":"1.0","type":"link"}