{"product_id":"labyrinth-b58-5-inch-downpipe","title":"Labyrinth B58 5 Inch Downpipe | BMW M140i, M240i, 340i, 440i","description":"\u003csection class=\"text-token-text-primary w-full focus:outline-none [--shadow-height:45px] has-data-writing-block:pointer-events-none has-data-writing-block:-mt-(--shadow-height) has-data-writing-block:pt-(--shadow-height) [\u0026amp;:has([data-writing-block])\u0026gt;*]:pointer-events-auto [content-visibility:auto] supports-[content-visibility:auto]:[contain-intrinsic-size:auto_100lvh] R6Vx5W_threadScrollVars scroll-mb-[calc(var(--scroll-root-safe-area-inset-bottom,0px)+var(--thread-response-height))] scroll-mt-[calc(var(--header-height)+min(200px,max(70px,20svh)))]\" dir=\"auto\" data-turn-id=\"request-WEB:06616443-24db-4d66-b289-1bcc3371bf10-34\" data-testid=\"conversation-turn-26\" data-scroll-anchor=\"false\" data-turn=\"assistant\"\u003e\n\u003cdiv class=\"text-base my-auto mx-auto pb-10 [--thread-content-margin:var(--thread-content-margin-xs,calc(var(--spacing)*4))] @w-sm\/main:[--thread-content-margin:var(--thread-content-margin-sm,calc(var(--spacing)*6))] @w-lg\/main:[--thread-content-margin:var(--thread-content-margin-lg,calc(var(--spacing)*16))] px-(--thread-content-margin)\"\u003e\n\u003cdiv class=\"[--thread-content-max-width:40rem] @w-lg\/main:[--thread-content-max-width:48rem] mx-auto max-w-(--thread-content-max-width) flex-1 group\/turn-messages focus-visible:outline-hidden relative flex w-full min-w-0 flex-col agent-turn\"\u003e\n\u003cdiv class=\"flex max-w-full flex-col gap-4 grow\"\u003e\n\u003cdiv data-message-author-role=\"assistant\" data-message-id=\"76bbf3dd-7597-4b9c-812b-1a076e7f149b\" dir=\"auto\" data-message-model-slug=\"gpt-5-5-thinking\" class=\"min-h-8 text-message relative flex w-full flex-col items-end gap-2 text-start break-words whitespace-normal outline-none keyboard-focused:focus-ring [.text-message+\u0026amp;]:mt-1\" data-turn-start-message=\"true\" tabindex=\"0\"\u003e\n\u003cdiv class=\"flex w-full flex-col gap-1 empty:hidden\"\u003e\n\u003cdiv class=\"markdown prose dark:prose-invert w-full wrap-break-word dark markdown-new-styling\"\u003e\n\u003cp data-start=\"125\" data-end=\"463\"\u003eThe Labyrinth B58 5 Inch Downpipe is built for maximum exhaust flow, designed as the single least restrictive downpipe for the platform, it is the perfect supporting upgrade when paired with the Labyrinth B58 HPFP Kit.\u003c\/p\u003e\n\u003cp data-start=\"465\" data-end=\"488\"\u003e\u003cstrong data-start=\"465\" data-end=\"488\"\u003eProduct description\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp data-start=\"490\" data-end=\"795\"\u003eThe Labyrinth B58 5 Inch Downpipe is engineered for B58 owners who want serious flow capacity without sacrificing fitment, quality, or drivability. The large 5 inch design helps minimize exhaust restriction after the turbo, allowing the B58 to breathe more efficiently under higher boost and heavier load.\u003c\/p\u003e\n\u003cp data-start=\"797\" data-end=\"1216\"\u003eCompared to the factory downpipe, this setup is designed to reduce backpressure, support faster turbo response, and unlock a sharper, more aggressive exhaust note. Whether you are building a tuned street car, running ethanol blends, pushing higher boost, or preparing for an upgraded turbo setup, the Labyrinth 5 Inch Downpipe gives your exhaust system the flow capacity needed to support the next level of performance.\u003c\/p\u003e\n\u003cp data-start=\"1218\" data-end=\"1533\"\u003eFor the best complete setup, pair this downpipe with the \u003cstrong data-start=\"1275\" data-end=\"1307\"\u003eLabyrinth B58 Gen 1 HPFP Kit\u003c\/strong\u003e. Together, they support two of the most important areas on a tuned B58 build: fuel supply and exhaust flow. The HPFP kit helps feed the engine, while the 5 inch downpipe helps the turbo move exhaust out with less restriction. \u003c\/p\u003e\n\u003cp data-start=\"1535\" data-end=\"1706\"\u003eEvery Labyrinth downpipe is designed with fitment, durability, and performance in mind, giving your build a clean, purpose built upgrade that looks as good as it performs.\u003c\/p\u003e\n\u003cp data-start=\"1708\" data-end=\"1724\"\u003e\u003cstrong data-start=\"1708\" data-end=\"1724\"\u003eKey features\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp data-start=\"1726\" data-end=\"2269\"\u003e5 inch high flow construction\u003cbr data-start=\"1755\" data-end=\"1758\"\u003eDesigned as one of the least restrictive B58 downpipe options available\u003cbr data-start=\"1829\" data-end=\"1832\"\u003eHelps reduce post turbo exhaust restriction\u003cbr data-start=\"1875\" data-end=\"1878\"\u003eSupports improved turbo response and faster spool\u003cbr data-start=\"1927\" data-end=\"1930\"\u003eDeeper, sharper, more aggressive exhaust tone\u003cbr data-start=\"1975\" data-end=\"1978\"\u003eExcellent supporting upgrade for tuned B58 applications\u003cbr data-start=\"2033\" data-end=\"2036\"\u003eIdeal for ethanol blends, higher boost, and upgraded turbo setups\u003cbr data-start=\"2101\" data-end=\"2104\"\u003ePairs perfectly with the Labyrinth B58 Gen 1 HPFP Kit\u003cbr data-start=\"2157\" data-end=\"2160\"\u003eBuilt for clean fitment on compatible B58 models\u003cbr data-start=\"2208\" data-end=\"2211\"\u003eDesigned for performance focused street and track builds\u003c\/p\u003e\n\u003cp data-start=\"2271\" data-end=\"2282\"\u003e\u003cstrong data-start=\"2271\" data-end=\"2282\"\u003eFitment\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp data-start=\"2284\" data-end=\"2331\"\u003eDesigned for B58 powered BMW models, including:\u003c\/p\u003e\n\u003cp data-start=\"2333\" data-end=\"2389\"\u003eBMW M140i\u003cbr data-start=\"2342\" data-end=\"2345\"\u003eBMW M240i\u003cbr data-start=\"2354\" data-end=\"2357\"\u003eBMW 340i\u003cbr data-start=\"2365\" data-end=\"2368\"\u003eBMW 440i\u003cbr data-start=\"2376\" data-end=\"2379\"\u003eBMW 540i\u003c\/p\u003e\n\u003cp data-start=\"2391\" data-end=\"2500\"\u003eFitment may vary by chassis, model year, drivetrain, and market. Please verify compatibility before ordering.\u003c\/p\u003e\n\u003cp data-start=\"2502\" data-end=\"2511\"\u003e\u003cstrong data-start=\"2502\" data-end=\"2511\"\u003eNotes\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp data-start=\"2513\" data-end=\"2739\" data-is-last-node=\"\" data-is-only-node=\"\"\u003eProfessional installation and proper tuning are recommended for best results. This product may not be legal for street use in all areas. Buyer is responsible for confirming local emissions laws before purchase or installation.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"z-0 flex min-h-[46px] justify-start\"\u003e\u003cbr\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/section\u003e\n\u003cdiv aria-hidden=\"true\" class=\"pointer-events-none -mt-px h-px translate-y-[calc(var(--scroll-root-safe-area-inset-bottom)-14*var(--spacing))]\"\u003e\u003cbr\u003e\u003c\/div\u003e","brand":"My Store","offers":[{"title":"Default Title","offer_id":66723616653616,"sku":null,"price":275.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0967\/9542\/7120\/files\/Screenshot_2026-05-04_at_11.59.11_PM.png?v=1777953564","url":"https:\/\/labyrinthautomotive.com\/products\/labyrinth-b58-5-inch-downpipe","provider":"Labyrinth Performance","version":"1.0","type":"link"}