{"product_id":"hks-03-06-evo-8-9-1-2mm-stopper-head-gasket-86mm-bore-8-5-cr","title":"HKS 03-06 Evo 8\/9 1.2mm Stopper head gasket (86mm bore 8.5 cr)","description":"\u003cp\u003e\u003cstrong\u003eSKU:\u003c\/strong\u003e \u003cspan itemprop=\"sku\"\u003e23001-AM004\u003c\/span\u003e | \u003cstrong\u003eUPC:\u003c\/strong\u003e 4957266643020\u003c\/p\u003e\n\n\u003ch4\u003e\u003cstrong\u003eHKS 03-06 Evo 8\/9 1.2mm Stopper Head Gasket (86mm Bore 8.5 CR)\u003c\/strong\u003e\u003c\/h4\u003e\n\u003cp\u003eThis HKS Stopper Head Gasket provides exact compression control for 2003-2006 Mitsubishi Lancer Evolution 8 and 9 with 4G63T engines. The 1.2mm thickness and 86mm bore deliver 8.5:1 compression ratio suited to turbocharged performance builds. Stopper construction holds seal under boost pressures exceeding 30 psi in Evo racing applications.\u003c\/p\u003e\n\n\u003ch4\u003eKey Features\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eStopper Layer Construction:\u003c\/strong\u003e Reinforced center layer prevents blowout and seals during high cylinder pressures over 30 psi boost\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e1.2mm Thickness:\u003c\/strong\u003e Engineered to achieve 8.5:1 compression ratio with stock head or aftermarket parts\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e86mm Bore Diameter:\u003c\/strong\u003e Matches Evo 4G63 pistons for correct combustion chamber volume and power delivery\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMulti-Layer Steel Build:\u003c\/strong\u003e Three-layer MLS material resists heat and allows reuse in track environments\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHKS Precision Machining:\u003c\/strong\u003e Tolerances under 0.01mm ensure head-to-block fit that minimizes leaks and improves efficiency\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch4\u003eProduct Notes\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003eInspect and machine cylinder head and block surfaces to ensure flatness within 0.002 inches prior to installation\u003c\/li\u003e\n\u003cli\u003eTorque head bolts in sequence using moly paste and follow HKS or ARP specifications for longevity\u003c\/li\u003e\n\u003cli\u003eStore flat in original packaging away from moisture to preserve sealing edges\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\u003eRequires complete cylinder head removal and resurfacing for best results\u003c\/li\u003e\n\u003cli\u003eCompatible with HKS head studs or ARP 625+ kit for secure clamping under high boost\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\u003e2003-2005\u003c\/td\u003e\n\u003ctd\u003eMitsubishi\u003c\/td\u003e\n\u003ctd\u003eLancer\u003c\/td\u003e\n\u003ctd\u003eEvolution VIII (RS GSR MR FQ-300 FQ-360)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e2005-2006\u003c\/td\u003e\n\u003ctd\u003eMitsubishi\u003c\/td\u003e\n\u003ctd\u003eLancer\u003c\/td\u003e\n\u003ctd\u003eEvolution IX (RS GSR MR FQ-360)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch4\u003eWhy Choose HKS?\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003eProven in Super Taikyu and D1GP racing with Evo platforms for over 20 years\u003c\/li\u003e\n\u003cli\u003eManufactured in Japan with aerospace-grade materials for consistent high-RPM durability\u003c\/li\u003e\n\u003cli\u003eBacked by dyno-tested data showing 10% power gains in boosted 4G63 applications\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 Will this gasket fit 2006 Evo 9 MR with stock pistons?\u003cbr\u003e\n      \u003cstrong\u003eA:\u003c\/strong\u003e Yes it directly fits all 2003-2006 Evo 8\/9 variants including MR models with 86mm bore 4G63T engines for immediate 8.5:1 CR upgrade\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eQ:\u003c\/strong\u003e What material makes up the gasket layers?\u003cbr\u003e\n      \u003cstrong\u003eA:\u003c\/strong\u003e Triple-layer stainless steel with solid stopper bead and elastomeric coating for superior heat cycle resistance up to 1000 degrees F\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eQ:\u003c\/strong\u003e Does HKS offer a warranty on this head gasket?\u003cbr\u003e\n      \u003cstrong\u003eA:\u003c\/strong\u003e Covered under HKS limited lifetime warranty against manufacturing defects when installed by certified technicians\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 or USPS Priority\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 flat envelope 12 x 9 x 0.5 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight:\u003c\/strong\u003e 0.35 lbs\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"HKS","offers":[{"title":"Default Title","offer_id":43805362913359,"sku":"HKS23001-AM004","price":330.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1062\/7920\/files\/hks-03-06-evo-89-1_2mm-stopper-head-gasket-86mm-bore-8_5-cr-hks.jpg?v=1767419610","url":"https:\/\/www.blackopsautoworks.com\/products\/hks-03-06-evo-8-9-1-2mm-stopper-head-gasket-86mm-bore-8-5-cr","provider":"Black Ops Auto Works","version":"1.0","type":"link"}