{"product_id":"mad-bmw-s58-3-5-fatboy-x3m-x4m-f97-f98-downpipes","title":"MAD BMW S58 3.5'' FATBOY X3M \u0026 X4M F97 F98 Downpipes","description":"\u003cp\u003eTake your BMW X3M or X4M to the next level with the\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003eMAD 3.5\" FatBoy Catless Downpipes\u003c\/strong\u003e. Designed for enthusiasts who demand maximum performance, our latest FatBoy design features a massive\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003e3.5-inch diameter\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003efor significantly improved exhaust flow over traditional downpipes.\u003c\/p\u003e\n\u003cp\u003eEngineered specifically for the S58 platform, the MAD FatBoy Downpipes reduce exhaust backpressure, allowing the turbochargers to spool faster, improve throttle response, and unlock substantial horsepower and torque gains. Combined with an aggressive exhaust note and increased turbo sound, this is one of the most impactful upgrades you can make to your X3M or X4M.\u003c\/p\u003e\n\u003ch2 tabindex=\"-1\"\u003ePerformance Benefits\u003c\/h2\u003e\n\u003cp\u003eThe factory catalytic converters create a major restriction in the exhaust system. The MAD 3.5\" FatBoy Catless Downpipes eliminate this bottleneck, providing:\u003c\/p\u003e\n\u003cul class=\"ak-ul\"\u003e\n\u003cli\u003e\n\u003cp\u003eUp to\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003e30+ WHP\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eon stock turbochargers\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eEven greater gains with upgraded turbochargers\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eFaster turbo spool\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eSharper throttle response\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eReduced exhaust backpressure\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eIncreased horsepower and torque\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eLower exhaust temperatures\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eImproved overall driving experience\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2 tabindex=\"-1\"\u003eWhy the FatBoy Design?\u003c\/h2\u003e\n\u003cp\u003eUnlike conventional downpipes, the MAD\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003e3.5\" FatBoy\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003edesign maximizes exhaust volume immediately after the turbocharger, allowing exhaust gases to expand more efficiently for improved flow and performance.\u003c\/p\u003e\n\u003cp\u003eThe result is:\u003c\/p\u003e\n\u003cul class=\"ak-ul\"\u003e\n\u003cli\u003e\n\u003cp\u003eMaximum exhaust flow\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eImproved turbo efficiency\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eIncreased horsepower potential\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eMore aggressive exhaust tone\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eLouder turbo whistle\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2 tabindex=\"-1\"\u003ePremium Construction\u003c\/h2\u003e\n\u003cp\u003eEvery MAD FatBoy Downpipe is built to perform under the most demanding conditions.\u003c\/p\u003e\n\u003cp\u003eFeatures include:\u003c\/p\u003e\n\u003cul class=\"ak-ul\"\u003e\n\u003cli\u003e\n\u003cp\u003eMassive\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003e3.5-inch FatBoy design\u003c\/strong\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eHeavy-duty 304 stainless steel construction\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003ePrecision mandrel bends\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eTIG welded and hand-finished\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eSmooth internal transitions for unrestricted flow\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eIntegrated flex sections to reduce stress on the exhaust system\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003ePrecision CNC-machined flanges\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eDirect bolt-on installation\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eDesigned for both\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003eleft-hand drive (LHD)\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eand\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003eright-hand drive (RHD)\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003evehicles.\u003c\/p\u003e\n\u003ch2 tabindex=\"-1\"\u003eBuilt for Performance\u003c\/h2\u003e\n\u003cp\u003eWhether your vehicle is completely stock or running upgraded turbochargers, the MAD 3.5\" FatBoy Downpipes are designed to maximize performance while maintaining OEM-quality fitment.\u003c\/p\u003e\n\u003cp\u003eCompatible with both factory and most aftermarket exhaust systems, they deliver an aggressive exhaust note without unnecessary turbulence or restriction.\u003c\/p\u003e\n\u003ch2 tabindex=\"-1\"\u003eFeatures\u003c\/h2\u003e\n\u003cul class=\"ak-ul\"\u003e\n\u003cli\u003e\n\u003cp\u003eNEW\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003e3.5\" FatBoy design\u003c\/strong\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eCatless construction\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eMaximum exhaust flow\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eFaster turbo spool\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eSharper throttle response\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eUp to\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003e30+ WHP\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eon stock turbos\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eEven greater gains on upgraded turbos\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eMore aggressive exhaust tone\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eIncreased turbo whistle\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eHeavy-duty 304 stainless steel construction\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003ePrecision TIG welded\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eIntegrated flex sections\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eSpot-on fitment\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eCompatible with LHD and RHD vehicles\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eWorks with factory and aftermarket exhaust systems\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eLifetime Warranty against manufacturing defects and fitment\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eShips in 1–2 business days\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2 tabindex=\"-1\"\u003eInstallation Notes\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eDownpipe gaskets are not included.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eRequired for installation:\u003c\/p\u003e\n\u003cul class=\"ak-ul\"\u003e\n\u003cli\u003e\n\u003cp\u003eBMW Gasket\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003ePart #18308053348\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003e(Quantity: 2)\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2 tabindex=\"-1\"\u003eFitment\u003c\/h2\u003e\n\u003cul class=\"ak-ul\"\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003e2019+ BMW X3M (F97)\u003c\/strong\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003e2019+ BMW X4M (F98)\u003c\/strong\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2 tabindex=\"-1\"\u003eSKU\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eMAD-041\u003c\/strong\u003e\u003c\/p\u003e\n\u003chr role=\"presentation\"\u003e\n\u003ch2 tabindex=\"-1\"\u003eEmissions Disclaimer\u003c\/h2\u003e\n\u003cp\u003eThis product is\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003enot legal for sale or use on pollution-controlled vehicles operated on public roads, highways, or streets.\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eIt is intended for\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003eoff-road, race, or closed-course competition use only\u003c\/strong\u003e, where such modifications are permitted.\u003c\/p\u003e\n\u003cp\u003eBy purchasing this product, you acknowledge and agree that:\u003c\/p\u003e\n\u003cul class=\"ak-ul\"\u003e\n\u003cli\u003e\n\u003cp\u003eYou are responsible for complying with all applicable federal, state, and local emissions laws and regulations.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eMAD and its affiliates disclaim any liability for improper or unlawful use of this product.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eUse of this product on public roads may violate the\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003eFederal Clean Air Act (42 U.S.C. § 7522)\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eand similar state laws.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003ePlease verify your local emissions regulations before purchasing or installing this product.\u003c\/p\u003e","brand":"MAD","offers":[{"title":"Default Title","offer_id":50398455431405,"sku":null,"price":319.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0036\/6270\/8851\/files\/Screenshot2026-08-04at3.39.57PM.png?v=1785879624","url":"https:\/\/coloradon5x.com\/products\/mad-bmw-s58-3-5-fatboy-x3m-x4m-f97-f98-downpipes","provider":"COLORADO N5X","version":"1.0","type":"link"}