{"product_id":"bmw-s55-stage-1-built-short-block","title":"BMW S55 Stage 1 Built Short Block (Assembled Bottom End)","description":"\u003cp\u003e\u003cstrong\u003eOne assembled unit, in stock and ready to ship.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThis is a complete BMW S55 short block, built and measured in our Lake Forest, California shop. It's the Stage 1 build from our \u003ca href=\"https:\/\/langracing.com\/built-s55-engine-guide\/\"\u003eBuilt S55 Engine Guide\u003c\/a\u003e: CP forged pistons and Carrillo connecting rods on the factory crankshaft, with our keyed crank hub fitted. If you want forged internals without waiting on parts, machining and assembly, this is the shortcut.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat's included\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eOEM BMW S55 block\u003c\/li\u003e\n\u003cli\u003eOEM S55 crankshaft, micropolished\u003c\/li\u003e\n\u003cli\u003e84.05 mm \u003ca href=\"\/products\/cp-forged-piston-set-bmw-s55\"\u003eCP forged pistons\u003c\/a\u003e with CP rings\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"\/products\/carrillo-s55-connecting-rod-set-of-6\"\u003eCarrillo connecting rods\u003c\/a\u003e with WMC rod bolts\u003c\/li\u003e\n\u003cli\u003eACL Race Series \u003ca href=\"\/products\/acl-bmw-n54-n55-s55b30-3-0l-standard-size-main-bearing-set\"\u003emain bearings\u003c\/a\u003e and \u003ca href=\"\/products\/acl-rod-bearings-bmw-f80-f82-m3-n54-n55-s55\"\u003erod bearings\u003c\/a\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"\/products\/lang-racing-s55-keyed-crank-hub-kit-m3-m4-m2c\"\u003eLang Racing keyed crank hub\u003c\/a\u003e, fitted to the crankshaft\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eOnly the parts listed above are included. The cylinder head, head gasket, head studs, timing components, oil pump and oil pan are not.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eMeasured and documented\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eEvery measurement is on the three-page build sheet in the photos. The highlights:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eMain bearing clearance: 0.0023–0.0025\"\u003c\/li\u003e\n\u003cli\u003eRod bearing clearance: 0.0026–0.0028\"\u003c\/li\u003e\n\u003cli\u003ePiston-to-wall clearance: 0.0050–0.0055\"\u003c\/li\u003e\n\u003cli\u003eRing end gaps: top 0.019\", second 0.028–0.029\"\u003c\/li\u003e\n\u003cli\u003eRod side clearance: 0.007–0.009\"\u003c\/li\u003e\n\u003cli\u003eCrankshaft runout 0.0006\", end play 0.006\"\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eThe main bearing and piston-to-wall clearances run a little looser than BMW's factory numbers on purpose. \u003ca href=\"https:\/\/langracing.com\/built-s55-engine-guide\/\"\u003eOur guide\u003c\/a\u003e explains why.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eHead gasket\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe pistons sit 0.004–0.006\" above the block deck, so use the OEM BMW 1.20 mm head gasket (BMW 11127849620) or thicker. With the 1.20 mm gasket, squish measures 0.041–0.043\".\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eFits\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eBMW S55: F80 M3, F82\/F83 M4 and F87 M2 Competition.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eFinish the engine\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eA cylinder head: our \u003ca href=\"\/products\/s55-stage-1-performance-cylinder-head\"\u003eStage 1\u003c\/a\u003e, \u003ca href=\"\/products\/s55-stage-2-performance-cylinder-head\"\u003eStage 2\u003c\/a\u003e or \u003ca href=\"\/products\/s55-stage-3-performance-cylinder-head\"\u003eStage 3\u003c\/a\u003e head. We start recommending Stage 2 at around 650 hp.\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/products\/pro-series-bmw-s55-engine-oem-cylinder-head-stud-set\"\u003ePro Series S55 head studs\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003eA proper tune. Start on a stock tune, then have it tuned before adding boost. We tune in-house on our Mustang dyno and offer \u003ca href=\"\/products\/bootmod3-s55-bmw-f80-f82-m3-m4-f87-m2-competition-tune\"\u003ecustom bootmod3 tuning\u003c\/a\u003e.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eShipping and terms\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eShips crated by freight from Lake Forest, California, to the lower 48 states: $550 flat, crate included.\u003c\/li\u003e\n\u003cli\u003eOne unit available. Want one built to your spec? Call us.\u003c\/li\u003e\n\u003cli\u003eAll sales final. This is a one-off assembled unit, sold as documented in its build sheet.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eQuestions about fitment, or what else you'll need? Call us at \u003ca href=\"tel:+19496674397\"\u003e949-667-4397\u003c\/a\u003e.\u003c\/p\u003e","brand":"Lang Racing","offers":[{"title":"Default Title","offer_id":67891329564896,"sku":"LRD-S55-SB-001","price":13722.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0609\/7050\/0320\/files\/s-l1600_b73cb0b7-48ef-4680-90fd-68253deedb77.jpg?v=1791824504","url":"https:\/\/store.langracing.com\/products\/bmw-s55-stage-1-built-short-block","provider":"Lang Racing","version":"1.0","type":"link"}