{"product_id":"stone-exhaust-bmw-b58d-g14-g20-gpf-catless-downpipe-m340i-840i","title":"Stone Exhaust A223P B58D OPF\/GPF Delete Catless Downpipe De-Cat Turbo Front Pipe for Toyota GR Supra A90 3.0, BMW 3 Series G20\/G21 M340i xDrive, Z4 M40i G29 – Primary Cat Delete\/Race Pipe","description":"\u003cdiv class=\"product__description rte\"\u003e\n  \u003ch2\u003eStone Exhaust B58D OPF GPF De-cat Front Pipe for GR Supra A90, BMW 3 Series G20 G21 340i and Z4 G29 M40i — Part Number A223P\u003c\/h2\u003e\n\n  \u003cp\u003e\n    Unlock serious flow and sound on OPF equipped B58D cars with Stone Exhaust’s A223P turbo front pipe. This high flow de-cat pipe replaces the primary catalyst on Euro 6 particulate filter variants, releasing sharper throttle response, quicker turbo spool and a deeper, motorsport tone while retaining a straight bolt-on install to the factory turbo and stock system. Perfect upgrade for Toyota Supra MK5 A90 3.0, BMW M340i G20 G21 including xDrive, and BMW Z4 M40i G29 running the B58D with GPF.\n  \u003c\/p\u003e\n\n  \u003cp\u003e\n    We fit these in-house at MJ Modifications and run Stone hardware on our own B58 projects. Fitment is spot on, weld quality is superb and customer satisfaction has been consistently excellent. If you are hunting for a Supra A90 de-cat pipe, 340i G20 race down pipe, M340i xDrive turbo outlet or Z4 M40i G29 straight-through front pipe for OPF cars, this is the premium solution.\n  \u003c\/p\u003e\n\n  \u003ch3\u003eWhy choose this A223P de-cat front pipe\u003c\/h3\u003e\n  \u003cul\u003e\n    \u003cli\u003eDesigned specifically for B58D OPF GPF variants for maximum gas velocity and reduced back pressure\u003c\/li\u003e\n    \u003cli\u003eDirect fit to OE turbo housing and factory exhaust — no cutting, no additional fabrication\u003c\/li\u003e\n    \u003cli\u003eDistinct flex section helps absorb heat expansion and vibration to minimise fatigue\u003c\/li\u003e\n    \u003cli\u003eReinforced turbo flange with crisscross welds for durability under high load\u003c\/li\u003e\n    \u003cli\u003eSmooth, one piece bends for uninterrupted flow and minimal turbulence\u003c\/li\u003e\n    \u003cli\u003eRobotic welding for precise, repeatable build quality\u003c\/li\u003e\n    \u003cli\u003e3D scanned and reverse engineered from OEM parts for an exact factory-style install\u003c\/li\u003e\n    \u003cli\u003eBacked by a 2 year manufacturer warranty from Stone Exhaust\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003ch3\u003eEngineered for OPF-equipped B58D\u003c\/h3\u003e\n  \u003cp\u003e\n    Stone Exhaust developed the A223P using full reverse engineering of the Euro-spec B58D exhaust path. OEM components were 3D scanned to define optimal tube diameter, routing and bend geometry around the GPF layout seen on Supra A90, M340i and Z4 platforms. Computational analysis including flow modelling and thermal review was used to refine the path for real-world gains on OPF cars, delivering a responsive, freer-revving feel and a purposeful soundtrack.\n  \u003c\/p\u003e\n\n  \u003ch3\u003eBuild quality you can trust\u003c\/h3\u003e\n  \u003cul\u003e\n    \u003cli\u003eMulti-axis CNC bending for consistent roundness and smooth radii\u003c\/li\u003e\n    \u003cli\u003eDeep penetration robotic welds with overlapping techniques at high temperature joints\u003c\/li\u003e\n    \u003cli\u003eMinimal internal weld disturbance for clean exhaust gas transition\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003cp\u003e\n    The result is a high flow turbo pipe that installs like factory, withstands heat and abuse, and transforms the character of your B58D OPF vehicle.\n  \u003c\/p\u003e\n\n  \u003ch3\u003eCompatibility\u003c\/h3\u003e\n  \u003cp\u003e\u003cstrong\u003eEngine\u003c\/strong\u003e B58D with OPF GPF\u003c\/p\u003e\n  \u003cp\u003e\u003cstrong\u003eToyota\u003c\/strong\u003e\u003c\/p\u003e\n  \u003cul\u003e\n    \u003cli\u003eGR Supra A90 3.0 B58D with OPF GPF\u003c\/li\u003e\n  \u003c\/ul\u003e\n  \u003cp\u003e\u003cstrong\u003eBMW\u003c\/strong\u003e\u003c\/p\u003e\n  \u003cul\u003e\n    \u003cli\u003e3 Series G20 M340i and M340i xDrive B58D with OPF GPF\u003c\/li\u003e\n    \u003cli\u003e3 Series Touring G21 M340i xDrive B58D with OPF GPF\u003c\/li\u003e\n    \u003cli\u003eZ4 G29 M40i B58D with OPF GPF\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003ch3\u003ePart number and warranty\u003c\/h3\u003e\n  \u003cp\u003e\u003cstrong\u003ePart number\u003c\/strong\u003e A223P\u003c\/p\u003e\n  \u003cp\u003e\u003cstrong\u003eBrand\u003c\/strong\u003e Stone Exhaust\u003c\/p\u003e\n  \u003cp\u003e\u003cstrong\u003eWarranty\u003c\/strong\u003e 2 Years manufacturer warranty\u003c\/p\u003e\n\n  \u003ch3\u003eFitting and support\u003c\/h3\u003e\n  \u003cp\u003e\n    Professional installation recommended. MJ Modifications offers in-house fitting in Warwickshire. Request a fitted quote at\n    \u003ca href=\"mailto:info@mjmodifications.co.uk\"\u003einfo@mjmodifications.co.uk\u003c\/a\u003e.\n  \u003c\/p\u003e\n\n  \u003ch3\u003eSearch terms to help you find the right upgrade\u003c\/h3\u003e\n  \u003cp\u003e\n    Supra MK5 A90 3.0 de-cat pipe, Toyota J29 A90 turbo front pipe, B58 OPF GPF delete, B58D turbo outlet pipe, Euro 6 GPF down pipe, GR Supra race pipe, BMW 340i G20 de-cat front pipe, BMW M340i G20 G21 turbo down pipe, M340i xDrive G20 front pipe, Z4 G29 M40i straight pipe, B58D OPF performance exhaust upgrade, Stone A223P, high flow turbo pipe B58, Supra A90 primary cat delete, BMW G20 340i de-cat, Z4 M40i G29 exhaust front section, B58 GPF compatible de-cat front pipe.\n  \u003c\/p\u003e\n\n  \u003cp\u003e\u003cem\u003eFor off road or motorsport use only where local laws permit.\u003c\/em\u003e\u003c\/p\u003e\n\u003c\/div\u003e","brand":"Stone Exhaust","offers":[{"title":"Default Title","offer_id":55978564354434,"sku":null,"price":960.96,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0871\/5445\/8937\/files\/Downpipe-1-8T-Audi-TT-MK1-Golf-GTI-MK4-GLI-Jetta-New-Beetle-1-8T-3_jpg_Q90_jpg.webp?v=1763379780","url":"https:\/\/mjmodifications.co.uk\/products\/stone-exhaust-bmw-b58d-g14-g20-gpf-catless-downpipe-m340i-840i","provider":"MJ Modifications","version":"1.0","type":"link"}