{"product_id":"yella-terra-ls1-ls2-ultralite-1-8-8mm-shaft-rockers-yt6646","title":"Yella Terra GM LS1\/LS2 Ultralite 1.8:1 8mm Shaft-Mount Roller Rockers — YT 6646","description":"\u003cp\u003eYella Terra’s Ultralite shaft-mount roller rocker system is a lightweight factory-replacement\/street upgrade for GM LS1 and LS2 engines. This version uses a 1.8:1 rocker ratio with the factory-style 8 mm shaft mounting.\u003c\/p\u003e\u003ch3\u003eUltralite design\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eSet of 16 full-roller aluminium rocker arms.\u003c\/li\u003e\n\u003cli\u003eSupplier-rated to 400 lb maximum open spring pressure.\u003c\/li\u003e\n\u003cli\u003eApproximately 50% less oscillating nose weight than the factory rocker system.\u003c\/li\u003e\n\u003cli\u003eOversize full-complement caged bearings and precision-ground trunnions are designed specifically for oscillating rocker loads.\u003c\/li\u003e\n\u003cli\u003eAircraft-grade extruded aluminium arms reduce moving mass and help dissipate top-end heat.\u003c\/li\u003e\n\u003cli\u003eHardened chromoly roller tips reduce valve-tip and guide wear.\u003c\/li\u003e\n\u003cli\u003eCommon-shaft inlet\/exhaust mounting increases clamp footprint and valvetrain stability.\u003c\/li\u003e\n\u003cli\u003eMaximum spring diameter: 1.437 in.\u003c\/li\u003e\n\u003cli\u003eHydraulic operation; not recommended for flat-tappet or solid-lifter use.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eClearance requirements\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eYella Terra specifies a maximum recommended spring seat pressure of 380 lb for this Ultralite application.\u003c\/li\u003e\n\u003cli\u003eRequires Yella Terra YT 5132 10 mm valve-cover spacer.\u003c\/li\u003e\n\u003cli\u003eDue to variation in GM cylinder-head castings, localised head clearancing may be required. Clearance must be checked during installation.\u003c\/li\u003e\n\u003cli\u003eShaft centres must retain the applicable M8 mounting threads.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eInstallation:\u003c\/strong\u003e Verify pushrod length, rocker geometry, spring\/retainer clearance and piston-to-valve clearance for the complete engine combination.\u003c\/p\u003e\u003ch2\u003eProduct System\u003c\/h2\u003e\u003cul\u003e\u003cli\u003eEngine Parts\u003c\/li\u003e\u003c\/ul\u003e\u003ch2\u003eVehicle Fitment\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eChevrolet Corvette C5 Ls1\u003c\/li\u003e\n\u003cli\u003eChevrolet Corvette C6 Ls2\u003c\/li\u003e\n\u003cli\u003eHolden Commodore Ve Ls2\u003c\/li\u003e\n\u003cli\u003eHolden Commodore Vt Vt Ii Ls1\u003c\/li\u003e\n\u003cli\u003eHolden Commodore Vx Ls1\u003c\/li\u003e\n\u003cli\u003eHolden Commodore Vy Ls1\u003c\/li\u003e\n\u003cli\u003eHolden Commodore Vz Ls1\u003c\/li\u003e\n\u003cli\u003eHolden Commodore Vz Ls2\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eConfirm chassis, engine, drivetrain and production-year compatibility before ordering.\u003c\/p\u003e\u003ch2\u003eSupplier Part Number\u003c\/h2\u003e\u003cp\u003eYT 6646\u003c\/p\u003e\u003ch2\u003eBuilt by Boost \u0026amp; Tune Support\u003c\/h2\u003e\u003cp\u003eBBT can assist with fitment review, installation, supporting modifications, configuration and calibration requirements where applicable.\u003c\/p\u003e","brand":"Yella Terra","offers":[{"title":"Default Title","offer_id":43816977760323,"sku":"YT 6646","price":880.0,"currency_code":"AUD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0703\/0659\/4883\/files\/ULTRALITE__88406.1512707671.jpg?v=1789167606","url":"https:\/\/builtbyboostandtune.com.au\/products\/yella-terra-ls1-ls2-ultralite-1-8-8mm-shaft-rockers-yt6646","provider":"BUILT BY BOOST AND TUNE","version":"1.0","type":"link"}