{"product_id":"manley-chevrolet-small-block-exhaust-valve-kit-1-625in-head-dia-5-121in-o-a-length-0-3415in-stem","title":"Manley Chevrolet Small Block Exhaust Valve Kit - 1.625in Head Dia. 5.121in O\/A Length, 0.3415in Stem - 11571-8","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 1.625,+200\u003c\/li\u003e\n\u003cli\u003eExhaust, Valve-S\/D 1.625,+.200\u003c\/li\u003e\n\u003cli\u003eValve Length: 5.121\u003c\/li\u003e\n\u003cli\u003eValve Tip Length: 0.250\u003c\/li\u003e\n\u003cli\u003eTip Length: 0.250\u003c\/li\u003e\n\u003cli\u003eMargin Width: 0.070\u003c\/li\u003e\n\u003cli\u003eSeat Width: 0.100\u003c\/li\u003e\n\u003cli\u003eTop of Head: 25 Degree Dish\u003c\/li\u003e\n\u003cli\u003eValve Head Shape: 25 Degree Dish\u003c\/li\u003e\n\u003cli\u003eUnderhead Angle: 30.00\u003c\/li\u003e\n\u003cli\u003eUnderhead Radius: 1\/2\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\u003cli\u003eOut of Stock Message: Call for Availability\u003c\/li\u003e\n\u003cli\u003eTitle: Manley Valve - Exhaust, Valve-S\/D 1.625,+.200\u003c\/li\u003e\n\u003cli\u003eProp 65 Yes\/No: Yes\u003c\/li\u003e\n\u003cli\u003eProp 65 (C, R or CR): CR\u003c\/li\u003e\n\u003cli\u003eProp 65 - Short Label: Prop 65 Warning Label.JPG\u003c\/li\u003e\n\u003cli\u003eEngine Type: ICE\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Manley Performance","offers":[{"title":"Default Title","offer_id":52480977731947,"sku":"MAN11571-8","price":301.08,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0666\/9690\/4998\/files\/public_b2e244a4-1cbe-4689-b85d-633c03eab1bb.jpg?v=1778203243","url":"https:\/\/www.raptorracing.com\/products\/manley-chevrolet-small-block-exhaust-valve-kit-1-625in-head-dia-5-121in-o-a-length-0-3415in-stem","provider":"Raptor Racing","version":"1.0","type":"link"}