{"product_id":"s14-cylinder-head-service","title":"S14 Cylinder Head Service by 5150 AutoSport","description":"\u003cp\u003e\u003cstrong\u003e5150 AutoSport Performance Cylinder Head Services for BMW S14 Engines\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003e\u003cem\u003e\u003cspan style=\"color: rgb(255, 42, 0);\"\u003e\u003cstrong\u003ePlease note that price is based on customer providing core. If you need help sourcing a core, please \u003ca href=\"mailto:sales@5150autosport.com\"\u003econtact our sales team\u003c\/a\u003e.\u003c\/strong\u003e\u003c\/span\u003e\u003c\/em\u003e\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003eInvesting in a performance cylinder head service is crucial for optimizing engine potential in performance builds. We offer three levels of service to meet your budget and build goals, from OEM refresh to full race-level machining:\u003c\/p\u003e\n\u003ch3 data-start=\"703\" data-end=\"766\"\u003e\u003cstrong data-start=\"707\" data-end=\"764\"\u003eStage 1 – OEM Refresh (Rebuild \u0026amp; Reliability Focused)\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp data-start=\"767\" data-end=\"835\"\u003e\u003cem\u003eIdeal for stock or mildly modified engines needing a proper refresh.\u003c\/em\u003e\u003c\/p\u003e\n\u003cp data-start=\"837\" data-end=\"1417\"\u003eThe cylinder head is fully disassembled, cleaned, and soda blasted to remove carbon and contaminants. Valve guides are measured and inspected, with new guides installed if needed, then precision reamed and honed for proper clearance. A 5-angle valve job is performed to restore sealing efficiency, followed by resurfacing to ensure a flat, true mating surface. New Viton valve seals are installed, the head is fully reassembled using OEM valves, guides, springs, and retainers, and pressure tested after assembly.\u003cbr data-start=\"1350\" data-end=\"1353\"\u003e\u003cem data-start=\"1353\" data-end=\"1417\"\u003eOptional service upgrade: add a \u003ca href=\"https:\/\/5150autosport.com\/collections\/valve-spring-kits?filter.v.m.mm-google-shopping.custom_label_0=S14\u0026amp;sort_by=best-selling\"\u003ehigh-performance valve spring kit\u003c\/a\u003e.\u003c\/em\u003e\u003c\/p\u003e\n\u003cp data-start=\"837\" data-end=\"1417\"\u003e\u003cstrong\u003e\u003cem data-start=\"1353\" data-end=\"1417\"\u003eStage 1 at a Glance: \u003c\/em\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli data-start=\"837\" data-end=\"1417\"\u003eDisassemble and Clean\u003c\/li\u003e\n\u003cli data-start=\"837\" data-end=\"1417\"\u003eSoda Blast\u003c\/li\u003e\n\u003cli data-start=\"837\" data-end=\"1417\"\u003eInspect and Measure Valve Guides\n\u003cul\u003e\n\u003cli data-start=\"837\" data-end=\"1417\"\u003eRemoval and Installation of new Guides, if necessary\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003eReam and Hone Valve Guides\u003c\/li\u003e\n\u003cli\u003e5-Angle Valve Job\u003c\/li\u003e\n\u003cli\u003eResurfacing\u003c\/li\u003e\n\u003cli\u003eFinal Wash\u003c\/li\u003e\n\u003cli\u003eInstall New Viton Valve Seals\u003c\/li\u003e\n\u003cli\u003eSetting of Seat Pressure\u003c\/li\u003e\n\u003cli\u003eFull Reassembly\u003c\/li\u003e\n\u003cli\u003ePressure Testing after assembly\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3 data-start=\"703\" data-end=\"766\"\u003e\u003cstrong data-start=\"707\" data-end=\"764\"\u003eStage 2 – \u003cspan\u003ePerformance Valvetrain Upgrade\u003c\/span\u003e\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp data-start=\"1475\" data-end=\"1522\"\u003e\u003cem\u003eFor higher RPM builds and increased durability.\u003c\/em\u003e\u003c\/p\u003e\n\u003cp data-start=\"1524\" data-end=\"1834\"\u003eIncludes everything from \u003cstrong data-start=\"1549\" data-end=\"1560\"\u003eStage 1\u003c\/strong\u003e\u003cstrong\u003e, plus upgraded high-performance valves, a high-performance valve spring kit, and new valve locks\/keepers.\u003c\/strong\u003e This stage improves valvetrain stability, reduces the risk of valve float, and prepares the head for more aggressive use while retaining OEM-style machining processes.\u003c\/p\u003e\n\u003cp data-start=\"837\" data-end=\"1417\"\u003e\u003cstrong\u003e\u003cem data-start=\"1353\" data-end=\"1417\"\u003eStage 2 at a Glance: \u003c\/em\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli data-start=\"837\" data-end=\"1417\"\u003eDisassemble and Clean\u003c\/li\u003e\n\u003cli data-start=\"837\" data-end=\"1417\"\u003eSoda Blast\u003cbr\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"837\" data-end=\"1417\"\u003eRemoval of OEM Valve Guides\u003c\/li\u003e\n\u003cli data-start=\"837\" data-end=\"1417\"\u003eInstallation of Performance Valve Guides\u003c\/li\u003e\n\u003cli\u003eReam and Hone Valve Guides\u003c\/li\u003e\n\u003cli\u003e5-Angle Valve Job\u003c\/li\u003e\n\u003cli\u003eResurfacing\u003c\/li\u003e\n\u003cli\u003eFinal Wash\u003c\/li\u003e\n\u003cli\u003eInstall New Viton Valve Seals\u003c\/li\u003e\n\u003cli\u003eInstall New High Performance Valve Spring Kit\u003c\/li\u003e\n\u003cli\u003eInstall New High Performance Valve Kit\u003c\/li\u003e\n\u003cli\u003eInstall New High Performance Valve Keepers\u003c\/li\u003e\n\u003cli\u003eSetting of Seat Pressure\u003c\/li\u003e\n\u003cli\u003eFull Reassembly\u003c\/li\u003e\n\u003cli\u003ePressure Testing after assembly\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3 data-start=\"703\" data-end=\"766\"\u003e\u003cstrong data-start=\"707\" data-end=\"764\"\u003ePro-Xtreme – All-Out Performance Cylinder Head Service\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp data-start=\"1906\" data-end=\"1977\"\u003e\u003cem\u003eDesigned for high-horsepower, forced-induction, and competition builds.\u003c\/em\u003e\u003c\/p\u003e\n\u003cp data-start=\"1979\" data-end=\"2938\"\u003eThe cylinder head undergoes complete disassembly, cleaning, and in-depth inspection, including crack, leak, and pressure testing. Factory valve guides are replaced with high-performance guides, then precision reamed and honed for extreme heat and RPM stability. \u003c\/p\u003e\n\u003cp data-start=\"1979\" data-end=\"2938\"\u003eCNC multi-angle porting is performed on both intake and exhaust ports to improve airflow consistency across all cylinders. A CNC multi-angle intake valve job and radius exhaust valve job optimize flow into and out of the combustion chamber. Valves are unshrouded to further enhance airflow, and preventative chamfering is applied in critical areas to reduce stress concentrations.\u003c\/p\u003e\n\u003cp data-start=\"1979\" data-end=\"2938\"\u003eThe mating surface is trueness checked, resurfaced, and verified again for perfect sealing. After machining, the head is thoroughly washed and assembled using balanced and blueprint-matched high-performance valves, along with balanced valve springs and retainers for precise valve control and long-term durability.\u003c\/p\u003e\n\u003cp data-start=\"837\" data-end=\"1417\"\u003e\u003cstrong\u003e\u003cem data-start=\"1353\" data-end=\"1417\"\u003ePro-Xtreme at a Glance: \u003c\/em\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli data-start=\"837\" data-end=\"1417\"\u003eDisassemble and Clean\u003c\/li\u003e\n\u003cli data-start=\"837\" data-end=\"1417\"\u003eSoda Blast\u003cbr\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"837\" data-end=\"1417\"\u003eRemoval of OEM Valve Guides\u003c\/li\u003e\n\u003cli data-start=\"837\" data-end=\"1417\"\u003eInstallation of Performance Valve Guides\u003c\/li\u003e\n\u003cli\u003eReam and Hone Valve Guides\u003c\/li\u003e\n\u003cli\u003e5-Axis CNC Intake Porting\u003c\/li\u003e\n\u003cli\u003e5-Axis CNC Exhaust Porting\u003c\/li\u003e\n\u003cli\u003eCNC Combustion Chamber Modification\u003c\/li\u003e\n\u003cli\u003e\n\u003cmeta charset=\"utf-8\"\u003e5-Angle CNC Intake Valve Job\u003c\/li\u003e\n\u003cli\u003e\n\u003cmeta charset=\"utf-8\"\u003e5-Angle CNC Exhaust Valve Job\u003cbr\u003e\n\u003c\/li\u003e\n\u003cli\u003eUnshrouding of Valves\u003c\/li\u003e\n\u003cli\u003ePreventative Chamfering in Potential Problem Areas\u003c\/li\u003e\n\u003cli\u003eTrueness Checking of Mating Surface\u003c\/li\u003e\n\u003cli\u003eResurfacing\u003c\/li\u003e\n\u003cli\u003eFinal Wash\u003c\/li\u003e\n\u003cli\u003eInstall New Viton Valve Seals\u003cbr\u003e\n\u003c\/li\u003e\n\u003cli\u003eInstall New High Performance Valve Spring Kit\u003c\/li\u003e\n\u003cli\u003eInstall New High Performance Valve Kit\u003c\/li\u003e\n\u003cli\u003eInstall New High Performance Valve Keepers\u003c\/li\u003e\n\u003cli\u003e\n\u003cmeta charset=\"utf-8\"\u003eSetting of Seat Pressure\u003c\/li\u003e\n\u003cli\u003eFull Reassembly\u003c\/li\u003e\n\u003cli\u003ePressure Testing after Assembly\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cem\u003e\u003cstrong\u003eRead more about our Pro-Xtreme service \u003ca href=\"https:\/\/5150autosport.com\/blogs\/product-faq\/5150-pro-xtreme-cylinder-head-services\"\u003ehere\u003c\/a\u003e. \u003c\/strong\u003e\u003c\/em\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ciframe title=\"YouTube video player\" src=\"https:\/\/www.youtube.com\/embed\/F0_2xENSHKY?si=NiO2ktNtUdHj0CxZ\" height=\"315\" width=\"560\"\u003e\u003c\/iframe\u003e\u003c\/p\u003e\n\u003ch4\u003e\u003cstrong\u003eBMW S14 Applications:\u003c\/strong\u003e\u003c\/h4\u003e\n\u003cp\u003e\u003cstrong\u003eBMW S14B20\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp style=\"padding-left: 40px;\"\u003e1989-1991      E30     320is [Portugal and Italy]\u003cbr\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eBMW S14B23\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp style=\"padding-left: 40px;\"\u003e1986-1991      E30     M3\u003cbr\u003e1986-1987      E30     M3 Evo I\u003cbr\u003e1988      E30     M3 Evo II\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eBMW S14B25\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp style=\"padding-left: 40px;\"\u003e1990      E30     M3 Sport Evo (Evo III)\u003c\/p\u003e\n\u003cp\u003e\u003cem\u003e\u003cstrong\u003ePhotos for reference only - B48 cylinder head pictured\u003c\/strong\u003e\u003c\/em\u003e\u003c\/p\u003e\n\u003c!----\u003e","brand":"5150 AutoSport","offers":[{"title":"Stage 1","offer_id":53018775159091,"sku":"5150-CH-S14-S1","price":1000.0,"currency_code":"USD","in_stock":true},{"title":"Stage 2","offer_id":53018775191859,"sku":"5150-CH-S14-S2","price":2500.0,"currency_code":"USD","in_stock":true},{"title":"Pro-Xtreme","offer_id":53018775224627,"sku":"5150-CH-S14-XT","price":3800.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0735\/3827\/3587\/files\/BMW-S14-Cylinder-Head-in-Rottler-5-Axis-CNC-Machine.webp?v=1736192962","url":"https:\/\/5150autosport.com\/es\/products\/s14-cylinder-head-service","provider":"5150 AutoSport","version":"1.0","type":"link"}