{"product_id":"manley-chevy-lt-1-1-590-head-diameter-pro-flo-exhaust-valves-set-of-8","title":"Manley Chevy LT-1 1.590 Head Diameter Pro Flo Exhaust Valves (Set of 8)","description":"\u003cp\u003e\u003cstrong\u003eSKU:\u003c\/strong\u003e \u003cspan itemprop=\"sku\"\u003e12349-8\u003c\/span\u003e | \u003cstrong\u003eUPC:\u003c\/strong\u003e 807298086057\u003c\/p\u003e\n\n\u003ch4\u003e\u003cstrong\u003eManley Chevy LT-1 1.590 Head Diameter Pro Flo Exhaust Valves (Set of 8) 1969-1982 Small Block Chevy LT1 Heads\u003c\/strong\u003e\u003c\/h4\u003e\n\u003cp\u003eManley Pro Flo exhaust valves deliver high-flow performance for Chevy Small Block LT1 cylinder heads found on 1969-1982 Camaro Corvette and other models. This set of 8 valves with 1.590 inch head diameter suits Top Fuel Funny Car drag racers Big Block Chevy marine setups and Small Block Chevy circle track engines with restricted carbs. Engineered with swirl polishing these valves increase exhaust flow while handling extreme duty conditions.\u003c\/p\u003e\n\n\u003ch4\u003eKey Features\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSwirl Polished Design:\u003c\/strong\u003e Computer controlled process adds 10 percent more exhaust flow compared to standard polished valves for better engine breathing and power\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUndercut Stem Tip:\u003c\/strong\u003e Proprietary Manley tip design reduces valve guide wear and friction during high RPM operation\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStainless Steel Construction:\u003c\/strong\u003e Extreme duty XH-426 stainless steel withstands heat and stress in racing and marine environments\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePrecise Dimensions:\u003c\/strong\u003e 1.590 inch head diameter 4.910 inch length 11\/32 inch stem and 0.080 inch margin ensure drop-in fit for LT1 heads\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSet of Eight:\u003c\/strong\u003e Complete exhaust valve kit covers one V8 engine for full performance upgrade\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch4\u003eProduct Notes\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003eInspect cylinder head valve seats and guides before installation\u003c\/li\u003e\n\u003cli\u003eApply valve seat compound during break-in for longest life\u003c\/li\u003e\n\u003cli\u003eSpecial order item expect 3-5 business days processing time\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch4\u003eInstallation Notes\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003eProfessional installation recommended.\u003c\/li\u003e\n\u003cli\u003eValve job required to match swirl polished profile and margins\u003c\/li\u003e\n\u003cli\u003eCompatible with stock LT1 head hardware and aftermarket springs up to 180 lbs seat pressure\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch4\u003eThis Part Fits\u003c\/h4\u003e\n\u003ctable border=\"1\"\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003eYear\u003c\/th\u003e\n\u003cth\u003eMake\u003c\/th\u003e\n\u003cth\u003eModel\u003c\/th\u003e\n\u003cth\u003eSubmodel\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e1969\u003c\/td\u003e\n\u003ctd\u003eChevrolet\u003c\/td\u003e\n\u003ctd\u003eCamaro\u003c\/td\u003e\n\u003ctd\u003eZ28\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e1970\u003c\/td\u003e\n\u003ctd\u003eChevrolet\u003c\/td\u003e\n\u003ctd\u003eCamaro\u003c\/td\u003e\n\u003ctd\u003eZ28\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e1970-1972\u003c\/td\u003e\n\u003ctd\u003eChevrolet\u003c\/td\u003e\n\u003ctd\u003eCorvette\u003c\/td\u003e\n\u003ctd\u003eLT1\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e1971-1972\u003c\/td\u003e\n\u003ctd\u003eChevrolet\u003c\/td\u003e\n\u003ctd\u003eCamaro\u003c\/td\u003e\n\u003ctd\u003eZ28\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e1963-1982\u003c\/td\u003e\n\u003ctd\u003eChevrolet\u003c\/td\u003e\n\u003ctd\u003eSmall Block\u003c\/td\u003e\n\u003ctd\u003eLT1 Heads\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch4\u003eWhy Choose Manley?\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003eTrusted by Top Fuel and Funny Car teams for proven racing results\u003c\/li\u003e\n\u003cli\u003eValves built to endure high heat and RPM in competition engines\u003c\/li\u003e\n\u003cli\u003ePrecision machined in USA for exact tolerances and reliability\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch4\u003e\u003cstrong\u003eFrequently Asked Questions\u003c\/strong\u003e\u003c\/h4\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eQ:\u003c\/strong\u003e Which cylinder heads are compatible with these valves?\u003cbr\u003e\n      \u003cstrong\u003eA:\u003c\/strong\u003e Designed for Chevrolet Small Block LT1 heads casting numbers 336299 487399 or equivalent aftermarket LT1 heads on 1969-1982 engines\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eQ:\u003c\/strong\u003e What material are these valves made from?\u003cbr\u003e\n      \u003cstrong\u003eA:\u003c\/strong\u003e High strength XH-426 stainless steel alloy for superior heat resistance and durability in extreme applications\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eQ:\u003c\/strong\u003e What is the warranty on Manley valves?\u003cbr\u003e\n      \u003cstrong\u003eA:\u003c\/strong\u003e Limited lifetime warranty against manufacturing defects when installed by certified engine builder\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch4\u003eShipping \u0026amp; Handling\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMethod:\u003c\/strong\u003e UPS Ground\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAvailability:\u003c\/strong\u003e In stock - ships same or next business day\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePackaging:\u003c\/strong\u003e Protective cardboard box 7 x 4 x 2 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight:\u003c\/strong\u003e 1.1 lbs\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Manley Performance","offers":[{"title":"Default Title","offer_id":41508235640911,"sku":"MAN12349-8","price":514.08,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1062\/7920\/files\/manley-chevy-lt-1-1_590-head-diameter-pro-flo-exhaust-valves-set-of-8-manley-performance.jpg?v=1772548761","url":"https:\/\/www.blackopsautoworks.com\/products\/manley-chevy-lt-1-1-590-head-diameter-pro-flo-exhaust-valves-set-of-8","provider":"Black Ops Auto Works","version":"1.0","type":"link"}