{"product_id":"holley-efi-ls-hi-flow-fuel-rail-kit-ls1-ls2-ls3-ls6-l99-intakes","title":"Holley EFI LS Hi-Flow Fuel Rail Kit – LS1, LS2, LS3, LS6 \u0026 L99 Intakes","description":"\u003cp\u003eThe \u003cstrong\u003eHolley EFI LS Hi-Flow Fuel Rail Kit\u003c\/strong\u003e is designed for GM LS engines using compatible LS1, LS2, LS3, LS6, and L99 factory-style intake manifolds. Manufactured by \u003cstrong\u003eHolley EFI\u003c\/strong\u003e, these billet aluminum fuel rails use a large 5\/8\" internal fuel passage to support the increased fuel demand of higher-horsepower naturally aspirated, boosted, and performance LS combinations.\u003c\/p\u003e\n\u003cp\u003eEach rail is machined for -8AN \/ 3\/4\"-16 O-ring fittings and includes -6AN adapters, giving builders flexibility when plumbing pumps, regulators, feed lines, and return-style EFI systems. The black anodized finish, laser-etched Holley EFI logo, included mounting brackets, and installation hardware make this a clean upgrade for LS swaps, race cars, off-road builds, and street performance applications using compatible factory intake manifolds.\u003c\/p\u003e\n\u003ch4\u003eIncludes:\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003e(2) Holley EFI Hi-Flow Fuel Rails\u003c\/li\u003e\n\u003cli\u003e(4) -6AN to 3\/4\"-16 O-Ring Adapters\u003c\/li\u003e\n\u003cli\u003eFuel Rail Mounting Brackets\u003c\/li\u003e\n\u003cli\u003eRequired Mounting Hardware\u003c\/li\u003e\n\u003cli\u003eRequired Seals\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eNote:\u003c\/strong\u003e Fuel injectors, fuel pressure regulator, fuel lines, and additional fuel system fittings are not included.\u003c\/p\u003e\n\u003chr\u003e\n\u003cdetails class=\"details\"\u003e\n\u003csummary\u003e\u003cstrong\u003eSpecifications\u003c\/strong\u003e \u003cspan class=\"svg-wrapper icon-plus\"\u003e \u003csvg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" fill=\"none\" viewbox=\"0 0 14 14\" height=\"14\" width=\"14\"\u003e\n        \u003cpath stroke-linecap=\"round\" stroke-width=\"var(--icon-stroke-width)\" stroke=\"currentColor\" d=\"M2.75 7H11.25\" class=\"vertical\"\u003e\u003c\/path\u003e\n        \u003cpath stroke-linecap=\"round\" stroke-width=\"var(--icon-stroke-width)\" stroke=\"currentColor\" d=\"M7 2.75L7 11.25\" class=\"horizontal\"\u003e\u003c\/path\u003e\n      \u003c\/svg\u003e \u003c\/span\u003e\u003c\/summary\u003e\n\u003cdiv class=\"details-content rte\"\u003e\n\u003ctable class=\"custom-specs-table\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003cth\u003eSpecification\u003c\/th\u003e\n\u003cth\u003eDetails\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eManufacturer\u003c\/td\u003e\n\u003ctd\u003eHolley EFI\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePart Number\u003c\/td\u003e\n\u003ctd\u003e534-209\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eProduct Type\u003c\/td\u003e\n\u003ctd\u003eEFI Fuel Rail Kit\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eEngine Family\u003c\/td\u003e\n\u003ctd\u003eGM LS\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCompatible Intake Families\u003c\/td\u003e\n\u003ctd\u003eLS1, LS2, LS3, LS6 \u0026amp; L99 Factory Intakes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFuel Injection Type\u003c\/td\u003e\n\u003ctd\u003ePort Injection\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFuel System Type\u003c\/td\u003e\n\u003ctd\u003eEFI\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMaterial\u003c\/td\u003e\n\u003ctd\u003eAluminum\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFinish\u003c\/td\u003e\n\u003ctd\u003eBright-Dip Black Anodized\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFuel Passage Diameter\u003c\/td\u003e\n\u003ctd\u003e5\/8\"\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRail Port Size\u003c\/td\u003e\n\u003ctd\u003e3\/4\"-16 O-Ring \/ -8AN Compatible\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eIncluded Adapters\u003c\/td\u003e\n\u003ctd\u003e(4) -6AN to 3\/4\"-16 O-Ring\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFittings Included\u003c\/td\u003e\n\u003ctd\u003e-6AN Adapter Fittings Included\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFuel Injectors Included\u003c\/td\u003e\n\u003ctd\u003eNo\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eGaskets \/ Seals Included\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eGrade\u003c\/td\u003e\n\u003ctd\u003ePerformance\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eEmission Code\u003c\/td\u003e\n\u003ctd\u003e5\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003chr\u003e\n\u003cdetails class=\"details\"\u003e\n\u003csummary\u003e\u003cstrong\u003eFitment\u003c\/strong\u003e \u003cspan class=\"svg-wrapper icon-plus\"\u003e \u003csvg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" fill=\"none\" viewbox=\"0 0 14 14\" height=\"14\" width=\"14\"\u003e\n        \u003cpath stroke-linecap=\"round\" stroke-width=\"var(--icon-stroke-width)\" stroke=\"currentColor\" d=\"M2.75 7H11.25\" class=\"vertical\"\u003e\u003c\/path\u003e\n        \u003cpath stroke-linecap=\"round\" stroke-width=\"var(--icon-stroke-width)\" stroke=\"currentColor\" d=\"M7 2.75L7 11.25\" class=\"horizontal\"\u003e\u003c\/path\u003e\n      \u003c\/svg\u003e \u003c\/span\u003e\u003c\/summary\u003e\n\u003cdiv class=\"details-content rte\"\u003e\n\u003cp\u003eDesigned for compatible \u003cstrong\u003eGM LS engines using LS1, LS2, LS3, LS6, and L99 factory intake manifolds\u003c\/strong\u003e.\u003c\/p\u003e\n\u003ctable class=\"custom-specs-table\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003cth\u003eEngine Size\u003c\/th\u003e\n\u003cth\u003eDisplacement\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e4.8L V8\u003c\/td\u003e\n\u003ctd\u003e294 CID\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e5.3L V8\u003c\/td\u003e\n\u003ctd\u003e325 CID\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e5.7L V8\u003c\/td\u003e\n\u003ctd\u003e346 CID\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e6.0L V8\u003c\/td\u003e\n\u003ctd\u003e364 CID\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e6.2L V8\u003c\/td\u003e\n\u003ctd\u003e376 CID\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e7.0L V8\u003c\/td\u003e\n\u003ctd\u003e427 CID\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch3\u003eFitment Notes\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eIntended for compatible LS1, LS2, LS3, LS6, and L99 factory intake manifold applications.\u003c\/li\u003e\n\u003cli\u003eEngine displacement alone does not guarantee fitment. Verify intake manifold style, injector spacing, and injector configuration before ordering.\u003c\/li\u003e\n\u003cli\u003eThe rails are machined for \u003cstrong\u003e-8AN \/ 3\/4\"-16 O-ring fittings\u003c\/strong\u003e and include four -6AN adapters.\u003c\/li\u003e\n\u003cli\u003eFuel injectors, regulator, supply hose, return hose, and additional plumbing are sold separately.\u003c\/li\u003e\n\u003cli\u003eFuel pump capacity, injector size, regulator capacity, line size, and fuel type should be matched as a complete system.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003chr\u003e\n\u003cdetails class=\"details\"\u003e\n\u003csummary\u003e\u003cb\u003eFAQ\u003c\/b\u003e\u003c\/summary\u003e\n\u003cdiv class=\"details-content rte\"\u003e\n\u003ch3\u003e1. What is the benefit of the 5\/8\" internal fuel passage?\u003c\/h3\u003e\n\u003cp\u003eThe larger fuel passage increases available fuel volume through the rail, helping support engines with higher fuel demand than a factory-style fuel rail was designed to handle.\u003c\/p\u003e\n\u003ch3\u003e2. How is this kit different from Holley's LS truck intake fuel rails?\u003c\/h3\u003e\n\u003cp\u003eThis kit is designed around compatible \u003cstrong\u003eLS1, LS2, LS3, LS6, and L99 factory intake manifolds\u003c\/strong\u003e. Holley's truck-intake fuel rail kit is intended for LS truck-style intake manifolds, so selecting the correct rail kit depends primarily on the intake manifold being used.\u003c\/p\u003e\n\u003ch3\u003e3. Can I use -8AN fuel lines with these rails?\u003c\/h3\u003e\n\u003cp\u003eYes. The rails are machined with 3\/4\"-16 O-ring ports compatible with -8AN fittings. The kit also includes four -6AN adapters for builders using smaller fuel line plumbing.\u003c\/p\u003e\n\u003ch3\u003e4. Are these fuel rails a good upgrade for boosted LS engines?\u003c\/h3\u003e\n\u003cp\u003eThey can be. The increased rail volume and AN-style plumbing options make them well suited to higher-flow EFI systems, including naturally aspirated, supercharged, and turbocharged LS combinations. Pump, injector, regulator, and line capacity must still be matched to the engine's total fuel demand.\u003c\/p\u003e\n\u003ch3\u003e5. Are fuel injectors included with the kit?\u003c\/h3\u003e\n\u003cp\u003eNo. Fuel injectors are sold separately so they can be sized for the engine's horsepower, fuel type, boost level, and intended use.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003chr\u003e","brand":"Holley","offers":[{"title":"Default Title","offer_id":56871449264294,"sku":"534-209","price":254.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0693\/8394\/6406\/files\/534-209-Holley-EFI-LS-Hi-Flow-Fuel-Rails-1.jpg?v=1785166194","url":"https:\/\/wideopendesign.com\/products\/holley-efi-ls-hi-flow-fuel-rail-kit-ls1-ls2-ls3-ls6-l99-intakes","provider":"Wide Open Design","version":"1.0","type":"link"}