{"product_id":"manley-chevrolet-big-block-exhaust-valve-kit-1-880in-head-dia-5-464in-o-a-length-0-3715in-stem","title":"Manley Chevrolet Big Block Exhaust Valve Kit - 1.880in Head Dia. 5.464in O\/A Length, 0.3715in Stem - 11525-8","description":"\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\u003ch3\u003eFeatures\u003c\/h3\u003e\u003cul\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\u003cli\u003eExotic alloys for superior tensile strength, reliability, and longevity\u003c\/li\u003e\n\u003cli\u003eSwirl polishing and machined faces improved airflow\/optimized efficiency\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eSpecs\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eManley Valve\u003c\/li\u003e\n\u003cli\u003eExhaust, Valve-S\/D 1.880,+100\u003c\/li\u003e\n\u003cli\u003eExhaust, Valve-S\/D 1.880,+.100\u003c\/li\u003e\n\u003cli\u003eProduct Market: Domestic\u003c\/li\u003e\n\u003cli\u003eHead Diameter: 1.880\u003c\/li\u003e\n\u003cli\u003eValve Head Diameter: 1.880\u003c\/li\u003e\n\u003cli\u003eStem Diameter: 0.3715\u003c\/li\u003e\n\u003cli\u003eValve Stem Diameter: 0.3715\u003c\/li\u003e\n\u003cli\u003eO\/A Length: 5.464\u003c\/li\u003e\n\u003cli\u003eValve Length: 5.464\u003c\/li\u003e\n\u003cli\u003eValve Tip Length: 0.220\u003c\/li\u003e\n\u003cli\u003eTip Length: 0.220\u003c\/li\u003e\n\u003cli\u003eMargin Width: 0.075\u003c\/li\u003e\n\u003cli\u003eSeat Width: 0.100\u003c\/li\u003e\n\u003cli\u003eTop of Head: 7 Degree Dish\u003c\/li\u003e\n\u003cli\u003eValve Head Shape: 7 Degree Dish\u003c\/li\u003e\n\u003cli\u003eUnderhead Angle: 12.00\u003c\/li\u003e\n\u003cli\u003eUnderhead Radius: 3\/8\u003c\/li\u003e\n\u003cli\u003eValve Series: Severe Duty? Series\u003c\/li\u003e\n\u003cli\u003eValve Material: Stainless Steel\u003c\/li\u003e\n\u003cli\u003eValve Type: Exhaust\u003c\/li\u003e\n\u003cli\u003eProduct Type: Engine Exhaust Valve Kit\u003c\/li\u003e\n\u003cli\u003eValve Quantity: 8\u003c\/li\u003e\n\u003cli\u003eEngine Valve Quantity: 8\u003c\/li\u003e\n\u003cli\u003eIndustry: Automotive\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Manley Performance","offers":[{"title":"Default Title","offer_id":52480973799787,"sku":"MAN11525-8","price":421.5,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0666\/9690\/4998\/files\/public_992300b8-09e7-4700-9983-3551e55040bf.jpg?v=1778203338","url":"https:\/\/www.raptorracing.ca\/products\/manley-chevrolet-big-block-exhaust-valve-kit-1-880in-head-dia-5-464in-o-a-length-0-3715in-stem","provider":"Raptor Racing","version":"1.0","type":"link"}