{"product_id":"stone-exhaust-bmw-b48-g02-x4-30i-xdrive-cat-back-valvetronic-exhaust-system","title":"Stone Valved Cat-Back\/Catback Exhaust for BMW X3 G01 \u0026 X4 G02 30i xDrive (B48\/B46 2.0T) - Active Valve\/Valvetronic Flap-Controlled Sports Performance Exhaust, OPF\/GPF\/PPF Compatible, Bolt-On No-Drone Upgrade","description":"\u003cdiv class=\"product__description rte\"\u003e\n  \u003carticle class=\"unreset\" data-scroll-scope=\"\"\u003e\n\n    \u003ch2\u003eSwitchable sports system for BMW G01 X3 30i xDrive and G02 X4 30i xDrive\u003c\/h2\u003e\n\n    \u003cp\u003e\n      Transform the character of your 2.0 turbo BMW with this valve-controlled centre and rear section, purpose-built for the B48 and B46 engines. Expect a deeper, richer soundtrack on demand, crisp throttle response and a precision fit that mirrors factory mounting points. Developed through 3D scanning, reverse engineering and in-house dyno work, it combines OEM-style integration with a true performance feel.\n    \u003c\/p\u003e\n\n    \u003ch3\u003eKey advantages\u003c\/h3\u003e\n    \u003cul\u003e\n      \u003cli\u003eFactory-style valve logic retained for everyday refinement and open-valve excitement when you want it\u003c\/li\u003e\n      \u003cli\u003eOptional Stone Valvetronic remote kit available for manual sound control via a handheld controller\u003c\/li\u003e\n      \u003cli\u003eAccurate fitment thanks to detailed 3D data capture and CAD-driven development\u003c\/li\u003e\n      \u003cli\u003eIn-house dyno tested for sharper response and a more engaging drive\u003c\/li\u003e\n      \u003cli\u003eTuned to minimise cabin drone compared to the standard system\u003c\/li\u003e\n      \u003cli\u003eOne-piece architecture with high precision mechanical welding for strength\u003c\/li\u003e\n      \u003cli\u003e7-axis CNC bending for smooth internal flow and durability at tight radii\u003c\/li\u003e\n      \u003cli\u003ePlug and play OBDII controller compatibility when pairing with the Valvetronic option\u003c\/li\u003e\n    \u003c\/ul\u003e\n\n    \u003ch3\u003eHow it sounds and feels\u003c\/h3\u003e\n    \u003cp\u003e\n      Valves closed delivers a refined tone for commuting and long motorway runs. Open the valves and you get a louder, crisper, motorsport-inspired note with pronounced upshift cracks and a fuller midrange. It is civilised when cruising, then genuinely exciting on B-roads with a noticeable lift in responsiveness.\n    \u003c\/p\u003e\n\n    \u003ch3\u003eOPF and GPF friendly options\u003c\/h3\u003e\n    \u003cp\u003e\n      Running a vehicle with a particulate filter fitted from factory. An OPF solution is available on request at no extra cost to allow installation without dashboard errors. No ECU coding required to clear OPF faults. For road use, please check local regulations.\n    \u003c\/p\u003e\n\n    \u003ch3\u003eEngineering that sets it apart\u003c\/h3\u003e\n    \u003cul\u003e\n      \u003cli\u003e3D scanning and reverse engineering for OEM-style hangers, flanges and clearances\u003c\/li\u003e\n      \u003cli\u003eFlow-optimised routing to reduce restriction and promote turbo spool\u003c\/li\u003e\n      \u003cli\u003e7-axis CNC bending to maintain cross-sectional integrity through bends\u003c\/li\u003e\n      \u003cli\u003eCrisscross and overlapping weld techniques at high-stress areas for longevity\u003c\/li\u003e\n      \u003cli\u003eDirect spot welding by mechanical welding arms for repeatable precision\u003c\/li\u003e\n    \u003c\/ul\u003e\n\n    \u003ch3\u003eFitment\u003c\/h3\u003e\n    \u003cp\u003eCompatible with the following petrol models:\u003c\/p\u003e\n    \u003cul\u003e\n      \u003cli\u003eG01 X3 30i xDrive 2017 onward\u003c\/li\u003e\n      \u003cli\u003eG02 X4 30i xDrive 2017 onward\u003c\/li\u003e\n    \u003c\/ul\u003e\n\n    \u003ch3\u003eReal-world feedback\u003c\/h3\u003e\n    \u003cp\u003e\n      We have installed these systems on customer cars and our own builds. The verdict is consistently positive. Excellent fit, high quality welds, proper switchable sound and no motorway drone. A brilliant upgrade for anyone seeking a confident, sporty tone with day-to-day comfort.\n    \u003c\/p\u003e\n\n    \u003ch3\u003eVideo\u003c\/h3\u003e\n    \u003cp\u003e\u003cstrong\u003eBMW G02 X4 30i xDrive B48 shown with catless downpipe and Stone Valvetronic cat back\u003c\/strong\u003e\u003c\/p\u003e\n    \u003cp\u003e\n      \u003ciframe allow=\"accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture\" allowfullscreen=\"\" frameborder=\"0\" width=\"100%\" height=\"480\" src=\"https:\/\/www.youtube.com\/embed\/by1Ejyx1RuY\"\u003e\u003c\/iframe\u003e\n    \u003c\/p\u003e\n\n    \u003ch3\u003eInstalled photos\u003c\/h3\u003e\n    \u003cdiv\u003e\n      \u003cimg alt=\"BMW G02 X4 30i xDrive sports exhaust installed - dual exit with twin tips\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0284\/6300\/5795\/files\/Stone_Exhaust_BMW_B48_G02_X4_30i_xDrive_Cat-Back_Valvetronic_Exhaust_System_Stone_Exhaust_USA_2048x2048.png?v=1598437653\"\u003e\n    \u003c\/div\u003e\n    \u003cdiv\u003e\n      \u003cimg alt=\"BMW G02 X4 30i xDrive rear section upgrade installed\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0284\/6300\/5795\/files\/Stone_Exhaust_BMW_B48_G02_X4_30i_xDrive_Cat-Back_Valvetronic_Exhaust_System_Stone_Exhaust_USA-1_2048x2048.png?v=1598437709\"\u003e\n    \u003c\/div\u003e\n    \u003cdiv\u003e\n      \u003cimg alt=\"BMW X4 30i switchable exhaust detail - valve housing and pipework\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0284\/6300\/5795\/files\/Stone_Exhaust_BMW_B48_G02_X4_30i_xDrive_Cat-Back_Valvetronic_Exhaust_System_Stone_Exhaust_USA-2_2048x2048.png?v=1598437804\"\u003e\n    \u003c\/div\u003e\n    \u003cdiv\u003e\n      \u003cimg alt=\"BMW G02 X4 underside - performance centre and rear section routing\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0284\/6300\/5795\/files\/Stone_Exhaust_BMW_B48_G02_X4_30i_xDrive_Cat-Back_Valvetronic_Exhaust_System_Stone_Exhaust_USA-3_2048x2048.png?v=1598437832\"\u003e\n    \u003c\/div\u003e\n    \u003cdiv\u003e\n      \u003cimg alt=\"Twin tailpipe finishers - BMW B48 2.0T switchable sports exhaust\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0284\/6300\/5795\/files\/Stone_Exhaust_BMW_B48_G02_X4_30i_xDrive_Cat-Back_Valvetronic_Exhaust_System_Stone_Exhaust_USA-4_2048x2048.png?v=1598437874\"\u003e\n    \u003c\/div\u003e\n\n    \u003ch3\u003eTechnical development\u003c\/h3\u003e\n    \u003cp\u003e\n      Engineers capture pipe diameter, routing and bend angles then simulate gas flow, heat load and pressure zones prior to production. The result is a precision system for G01 and G02 platforms that looks factory, fits perfectly and delivers a more engaging drive.\n    \u003c\/p\u003e\n    \u003cdiv\u003e\n      \u003cimg alt=\"R and D and 3D scanning for accurate fitment\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0284\/6300\/5795\/files\/1_9336c8b0-c9ea-4822-891c-83490f630707_2048x2048.jpg?v=1572705528\"\u003e\n    \u003c\/div\u003e\n    \u003cdiv\u003e\n      \u003cimg alt=\"7-axis CNC bending for smooth flow\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0284\/6300\/5795\/files\/bending_2048x2048.jpg?v=1572739395\"\u003e\n    \u003c\/div\u003e\n    \u003cdiv\u003e\n      \u003cimg alt=\"Welding quality close-up\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0284\/6300\/5795\/files\/Stone_Exhaust_Art_of_Welding_-_1_2048x2048.jpg?v=1572828150\"\u003e\n    \u003c\/div\u003e\n    \u003cdiv\u003e\n      \u003cimg alt=\"Direct spot welding for repeatability\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0284\/6300\/5795\/files\/Stone_Exhaust_Art_of_Welding_-_2_2048x2048.jpg?v=1572828178\"\u003e\n    \u003c\/div\u003e\n\n    \u003ch3\u003eFitting and support\u003c\/h3\u003e\n    \u003cp\u003e\n      Professional installation available at MJ Modifications in Warwickshire. Request a fitting quote at \u003ca href=\"mailto:info@mjmodifications.co.uk\"\u003einfo@mjmodifications.co.uk\u003c\/a\u003e. We are happy to help with guidance on G01 and G02 valve control setup, OPF solutions and general fitment.\n    \u003c\/p\u003e\n\n    \u003ch3\u003eWarranty\u003c\/h3\u003e\n    \u003cp\u003e\n      Stone Exhaust 2 year warranty.\n    \u003c\/p\u003e\n\n    \u003ch3\u003ePart numbers\u003c\/h3\u003e\n    \u003cul\u003e\n      \u003cli\u003eAP543B for B48 engine\u003c\/li\u003e\n      \u003cli\u003eAP543NB for B46 engine\u003c\/li\u003e\n    \u003c\/ul\u003e\n\n    \u003ch3\u003eSearch-friendly terms\u003c\/h3\u003e\n    \u003cp\u003e\n      BMW X3 30i performance system, BMW X4 30i sports exhaust, G01 X3 sound upgrade, G02 X4 sound upgrade, B48 2.0 turbo switchable exhaust, B46 2.0T active valve exhaust, BMW X3 centre and rear section, BMW X4 free flow rear section, valve controlled exhaust for BMW 2.0 petrol, flap controlled exhaust for BMW G series, switchable back box BMW 30i, performance tailpipes BMW X3 X4, G01 G02 exhaust with valve control, OPF friendly exhaust option, GPF compatible exhaust option, dyno developed BMW 30i exhaust, no drone BMW 30i exhaust, UK BMW exhaust specialist, Warwickshire BMW fitting, MJ Modifications BMW exhaust fitting, plug and play valve controller BMW, Valvetronic remote upgrade for BMW B48, BMW G01 G02 2017 onward performance exhaust.\n    \u003c\/p\u003e\n\n  \u003c\/article\u003e\n\u003c\/div\u003e","brand":"Stone Exhaust","offers":[{"title":"OEM Integrated Valve(s) \/ Flat Cut Gloss Carbon Fiber (102mm) \/ B48","offer_id":56005708382594,"sku":null,"price":2427.84,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0871\/5445\/8937\/files\/1020CG_FlatCutGlossCarbonFibre_102mm_1946x_3bbbdc40-910a-4958-8893-98337f751c3f.png?v=1764021716","url":"https:\/\/mjmodifications.co.uk\/products\/stone-exhaust-bmw-b48-g02-x4-30i-xdrive-cat-back-valvetronic-exhaust-system","provider":"MJ Modifications","version":"1.0","type":"link"}