{"product_id":"bmw-m340i-m440i-straight-downpipe-with-heat-shield-b58-3-0t-2018-2023-wstn-performance","title":"BMW M340i\/M440i Straight Downpipe with Heat Shield 2019-2023 (B58 G20) | WSTN Performance","description":"\u003cdiv class=\"wstn-product\"\u003e\n\u003ch1\u003eThe B58 is built for more. This downpipe lets it deliver.\u003c\/h1\u003e\n\u003cp\u003eThe BMW M340i and M440i sit at the intersection of performance and daily usability smooth power delivery, sharp chassis, and the B58 inline-six producing 382hp from the factory. That number grows considerably with the factory restriction removed. This WSTN Performance Straight Catless Downpipe replaces the OEM unit with a straight-through design, complete with an integrated heat shield to maintain thermal management under sustained performance driving. Designed specifically for M340i and M440i applications, this is the downpipe that forms the foundation of any serious B58 build. Built to order, quality checked in Perth, dispatched worldwide.\u003c\/p\u003e\n\u003ch1\u003eWhy Upgrade?\u003c\/h1\u003e\n\u003cp\u003e✅ Heat Shield Integrated: Factory-matched heat shielding protects surrounding components and transmission tunnel critical for sustained high-performance use.\u003c\/p\u003e\n\u003cp\u003e✅ Free-Flow Construction: Straight-through design eliminates catalytic restriction the single most impactful exhaust modification for the turbocharged B58.\u003c\/p\u003e\n\u003cp\u003e✅ Tune-Ready Platform: Forms the foundation for ECU tuning software gains are limited without removing this restriction first.\u003c\/p\u003e\n\u003cp\u003e✅ Stainless Steel: Corrosion-resistant, heat-resistant, precision TIG-welded for durability and a consistent fit.\u003c\/p\u003e\n\u003cp\u003e✅ Direct Bolt-On: Replaces factory downpipe at OEM mounting points no modification required.\u003c\/p\u003e\n\u003ch1\u003eKey Features \u0026amp; Specs\u003c\/h1\u003e\n\u003cp\u003e\u003cstrong\u003eMaterial:\u003c\/strong\u003e Stainless Steel corrosion resistant, built to last\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eConstruction:\u003c\/strong\u003e Precision mandrel-bent, TIG-welded joints\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eType:\u003c\/strong\u003e Catless straight-through with heat shield\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eHeat Shield:\u003c\/strong\u003e Integrated heat shielding included\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eFitment:\u003c\/strong\u003e Direct bolt-on OEM mounting points\u003c\/p\u003e\n\u003ch1\u003eFitment \u0026amp; Compatibility\u003c\/h1\u003e\n\u003cp\u003e✔️ BMW M340i \/ 330i (G20\/G21) 2018–2023 (B58, 3.0T)\u003c\/p\u003e\n\u003cp\u003e✔️ BMW M440i \/ 430i (G22\/G23) 2020–2023 (B58, 3.0T)\u003c\/p\u003e\n\u003cp\u003eDesigned for M340i and M440i with heat shield integration. Also fits non-M 330i and 430i B58 variants. Confirm your exact model before ordering.\u003c\/p\u003e\n\u003ch3\u003eTechnical Note\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eEmissions:\u003c\/strong\u003e Catless straight-through intended for track and competition use. Buyer is responsible for local emissions compliance. Check applicable regulations before fitting to road-registered vehicles.\u003c\/p\u003e\n\u003ch1\u003eWhat's In the Box\u003c\/h1\u003e\n\u003cp\u003e1 x WSTN Performance Catless Straight Downpipe with Heat Shield\u003c\/p\u003e\n\u003ch1\u003eInstallation\u003c\/h1\u003e\n\u003cp\u003e\u003cstrong\u003eDifficulty:\u003c\/strong\u003e 3\/5 Requires workshop lift and exhaust experience\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eTime Estimate:\u003c\/strong\u003e 1.5–2.5 Hours\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eMounting Type:\u003c\/strong\u003e Direct bolt-on to factory turbo outlet and mid-pipe flanges\u003c\/p\u003e\n\u003ch1\u003eWarranty \/ Shipping\u003c\/h1\u003e\n\u003ch3\u003eDISCLAIMER\u003c\/h3\u003e\n\u003cp\u003eWSTN Performance components are designed for track and competition use. To protect your build and ensure a perfect finish, we recommend professional installation by a certified specialist\/workshop. It is the buyer's responsibility to ensure modifications comply with local regulations.\u003c\/p\u003e\n\u003ch3\u003eWARRANTY\u003c\/h3\u003e\n\u003cp\u003eWe stand behind every product we sell. All WSTN Performance products carry a 1 year WSTN Performance warranty as standard. This covers any manufacturing defects, giving you total peace of mind that your upgrade is built to last. \u003ca href=\"\/en-sg\/policies\/refund-policy\"\u003eView our full Warranty policy page here.\u003c\/a\u003e\u003c\/p\u003e\n\u003ch3\u003eSHIPPING\u003c\/h3\u003e\n\u003cp\u003eWe offer tracked worldwide shipping on our entire catalogue. Products marked as “Built to Order” are handmade in 3–5 weeks (check the product page as lead times may vary), personally dispatched from our Perth WA facility. \u003ca href=\"\/en-sg\/policies\/shipping-policy\"\u003eView our full Shipping policy page here.\u003c\/a\u003e\u003c\/p\u003e\n\u003ch3\u003eRETURNS\u003c\/h3\u003e\n\u003cp\u003eWe offer returns on all products if items are damaged or there is something wrong. If we ever make a mistake, we'll cover the return shipping to make it right. \u003ca href=\"\/en-sg\/policies\/refund-policy\"\u003eView our full Return policy page here.\u003c\/a\u003e\u003c\/p\u003e\n\u003ch3\u003eSUPPORT\u003c\/h3\u003e\n\u003cp\u003eNeed a hand with fitment, shipping, or a return? Our Perth-based team is here to help you get your build perfect.\u003cbr\u003eEmail: \u003ca href=\"mailto:contact@wstnperformance.com\"\u003econtact@wstnperformance.com\u003c\/a\u003e\u003c\/p\u003e\n\u003ch1\u003eSound Clip\u003c\/h1\u003e\n\u003c\/div\u003e","brand":"WSTN Performance","offers":[{"title":"Default Title","offer_id":50164640710902,"sku":"WSTN-BMW-G20-G21-G22-CDP","price":456.0,"currency_code":"SGD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0656\/2955\/2886\/files\/wstn-b58-dp-heatshield-3.png?v=1779982475","url":"https:\/\/wstnperformance.com.au\/en-sg\/products\/bmw-m340i-m440i-straight-downpipe-with-heat-shield-b58-3-0t-2018-2023-wstn-performance","provider":"wstnperformance","version":"1.0","type":"link"}