{"product_id":"milltek-large-bore-downpipe-pair-for-bmw-f80-m3-f82-m4-ssxbm1030","title":"Milltek Large Bore Downpipe Pair for BMW F80 M3 F82 M4","description":"\u003cp\u003eMilltek Large Bore Downpipe Pair with Hi-Flow Sports Catalysts for BMW F80 M3 and F82 M4. Direct bolt-on upgrade fabricated in T304L stainless steel with mandrel-bent construction. Larger diameter than OEM reduces backpressure and increases exhaust scavenging efficiency, delivering measurable performance gains and refined sound character when paired with a Milltek cat-back exhaust system.\u003c\/p\u003e\n\u003cp\u003eHand-finished T304L stainless construction with CNC-formed flanges and OEM-style hangers. Hi-Flow Sports Catalysts maintain emissions compliance while maximizing flow. Stage 2 ECU remap required for optimal results. Installation requires two lambda sensor extensions (BMW part 18307851168, available from any BMW dealer). Uses factory bolt points—no welding or modification required.\u003c\/p\u003e\n\u003ch3\u003eFitment Details\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eBMW F80 M3 (2014-2018) with S55 engine\u003c\/li\u003e\n\u003cli\u003eBMW F82 M4 (2014-2018) with S55 engine\u003c\/li\u003e\n\u003cli\u003eRequires Milltek cat-back exhaust system for complete integration\u003c\/li\u003e\n\u003cli\u003eNot compatible with factory M Performance exhaust\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eFits Milltek Cat-Back.\u003c\/p\u003e\n\u003cp\u003eDesigned and manufactured in the UK with 40+ years of performance exhaust heritage. Tested at the Nurburgring.\u003c\/p\u003e\n\u003ch3\u003eVehicle fitment\u003c\/h3\u003e\n\u003cul class=\"fitment-list\"\u003e\n\u003cli\u003e2015-2018 BMW M3 Base\u003c\/li\u003e\n\u003cli\u003e2015-2018 BMW M4 Base\u003c\/li\u003e\n\u003cli\u003e2016 BMW M4 GTS\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Milltek","offers":[{"title":"Default Title","offer_id":60150694707486,"sku":"MILSSXBM1030","price":3596.27,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0759\/7965\/3406\/files\/SSXBM1030_1.jpg?v=1791254558","url":"https:\/\/shop.signatureautohaus.com\/products\/milltek-large-bore-downpipe-pair-for-bmw-f80-m3-f82-m4-ssxbm1030","provider":"Signature Autohaus","version":"1.0","type":"link"}