{"product_id":"stone-exhaust-bmw-n20-f30-f32-cat-back-valvetronic-exhaust-inc-328i-428i-1","title":"Stone Exhaust Valved Cat-Back Exhaust for BMW N20 F30 F32 F33 F36 (328i 428i) OEM Integrated Valve, Quad\/Dual\/Single Exit UK","description":"\u003cdiv\u003e\n  \u003ch2\u003eStone Exhaust BMW N20 F30 F32 OEM Integrated Valved Catback Exhaust System for 328i and 428i\u003c\/h2\u003e\n\n  \u003cp\u003eUpgrade your BMW 328i or 428i with the Stone Exhaust OEM Integrated Valved Catback Exhaust System and enjoy a deeper, sportier sound, OEM perfect fitment and proven performance. Designed specifically for the BMW N20 engine in the F30 3 Series and F32 F33 F36 4 Series, this valved cat back exhaust delivers everyday refinement with the excitement you expect when the valves open. If you are searching for BMW 328i exhaust, BMW 428i exhaust, BMW F30 catback, BMW F32 catback, N20 valved exhaust or quad exhaust for F30 and F32, this is the premium UK choice.\u003c\/p\u003e\n\n  \u003ch3\u003eWhy choose Stone Exhaust for your BMW 328i and 428i\u003c\/h3\u003e\n  \u003cul\u003e\n    \u003cli\u003eOEM integrated valve operation controlled by the factory ECU for seamless Comfort to Sport behaviour.\u003c\/li\u003e\n    \u003cli\u003eOptional Stone Valvetronic System Single Valve upgrade available for remote valve control via plug and play OBDII controller.\u003c\/li\u003e\n    \u003cli\u003eOne piece design for strength, durability and consistent flow.\u003c\/li\u003e\n    \u003cli\u003e3D scanning and reverse engineering of the OEM system for 100 percent OEM fitment and precision alignment.\u003c\/li\u003e\n    \u003cli\u003eDyno developed in house by Stone Exhaust for real, repeatable gains with the signature Stone sound.\u003c\/li\u003e\n    \u003cli\u003e7 axis CNC bending for exceptional roundness and accuracy, reducing turbulence and improving gas flow.\u003c\/li\u003e\n    \u003cli\u003eMechanical welding with precision including crisscross and overlapping techniques for endurance at high temperatures.\u003c\/li\u003e\n    \u003cli\u003eDirect spot welding by automated arms for superior penetration and consistency.\u003c\/li\u003e\n    \u003cli\u003eEliminates the drone found on the standard exhaust system for comfortable motorway cruising.\u003c\/li\u003e\n    \u003cli\u003eIn house research and development focused on flow, temperature and pressure optimisation.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003ch3\u003eHow the OEM integrated valve works\u003c\/h3\u003e\n  \u003cp\u003eThe OEM Integrated Valve option uses your car’s ECU to automatically open and close the exhaust valve. This preserves factory drivability and keeps things quiet when you want, then releases a richer, more aggressive note when you ask for performance.\u003c\/p\u003e\n  \u003cp\u003eWant full control at your fingertips? Add the Stone Valvetronic System Single Valve to operate the valve remotely. The plug and play OBDII controller makes installation straightforward.\u003c\/p\u003e\n\n  \u003ch3\u003eSound and performance you will love\u003c\/h3\u003e\n  \u003cp\u003eExpect a deeper tone, sharper throttle response and the iconic Stone Exhaust note without intrusive drone. This system is engineered to flow efficiently while maintaining daily refinement, making it perfect for spirited road use and long journeys alike.\u003c\/p\u003e\n\n  \u003ch3\u003eFitment and compatibility – BMW N20 engine\u003c\/h3\u003e\n  \u003cp\u003eBMW 3 Series\u003c\/p\u003e\n  \u003cul\u003e\n    \u003cli\u003eF30 328i 2011 onwards\u003c\/li\u003e\n  \u003c\/ul\u003e\n  \u003cp\u003eBMW 4 Series\u003c\/p\u003e\n  \u003cul\u003e\n    \u003cli\u003eF32 428i and 428i xDrive 2012 onwards\u003c\/li\u003e\n    \u003cli\u003eF33 428i and 428i xDrive 2013 onwards\u003c\/li\u003e\n    \u003cli\u003eF36 428i and 428i xDrive 2013 onwards\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003ch3\u003eOptions and part numbers\u003c\/h3\u003e\n  \u003cul\u003e\n    \u003cli\u003eAP501 Single Exit left with twin tailpipes\u003c\/li\u003e\n    \u003cli\u003eAP512 Dual Exit with single tailpipe\u003c\/li\u003e\n    \u003cli\u003eAP512Q Dual Exit with quad tailpipes\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003ch3\u003eFitted photos\u003c\/h3\u003e\n  \u003cp\u003eSee the Stone Exhaust BMW N20 F30 F32 F33 F36 cat back valved system installed:\u003c\/p\u003e\n  \u003cp\u003e\n    \u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0284\/6300\/5795\/files\/Untitled_826b0f54-3098-4016-a70e-08d0ad91eb69_600x600.png?v=1588851543\" alt=\"Stone Exhaust BMW F30 F32 N20 valved catback fitted dual exit with quad tailpipes\"\u003e\n  \u003c\/p\u003e\n  \u003cp\u003e\n    \u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0284\/6300\/5795\/files\/Untitled1_12e09e33-782b-4489-83be-55e14fcd1b2b_600x600.png?v=1588851554\" alt=\"Stone Exhaust BMW 328i 428i N20 cat back system UK\"\u003e\n  \u003c\/p\u003e\n  \u003cp\u003e\n    \u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0284\/6300\/5795\/files\/Untitled2_c23d2407-3ac1-4c70-a4a3-c1096e5563c2_600x600.png?v=1588851562\" alt=\"Stone Exhaust F30 F32 N20 quad tailpipes\"\u003e\n  \u003c\/p\u003e\n  \u003cp\u003e\n    \u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0284\/6300\/5795\/files\/Untitled3_838ccc82-7e14-4b0c-a505-216e47e9a94b_600x600.png?v=1588851570\" alt=\"Stone Exhaust BMW F30 F32 OEM integrated valved cat back UK\"\u003e\n  \u003c\/p\u003e\n\n  \u003ch3\u003eR\u0026amp;D and manufacturing\u003c\/h3\u003e\n  \u003cp\u003eStone Exhaust engineers 3D scan OEM parts to analyse pipe diameter, routing and bend angles, then simulate gas flow, thermal and pressure zones to refine performance. The result is an integrally moulded exhaust with accuracy to within 0.025 mm.\u003c\/p\u003e\n  \u003cp\u003e\n    \u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0284\/6300\/5795\/files\/1_9336c8b0-c9ea-4822-891c-83490f630707.jpg?v=1572705528\" alt=\"Stone Exhaust 3D scanning and reverse engineering BMW N20\"\u003e\n  \u003c\/p\u003e\n  \u003cp\u003eA 7 axis CNC bending machine achieves up to 98 percent roundness with low outer wall wear at tight bends, minimising flow loss and preventing weld fracture. Combined with crisscross and overlapping welding at high heat zones and precise direct spot welding, you get strength, reliability and a beautiful finish.\u003c\/p\u003e\n  \u003cp\u003e\n    \u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0284\/6300\/5795\/files\/bending.jpg?v=1572739395\" alt=\"Stone Exhaust CNC bending precision\"\u003e\n  \u003c\/p\u003e\n  \u003cp\u003e\n    \u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0284\/6300\/5795\/files\/Stone_Exhaust_Art_of_Welding_-_1_1024x1024.jpg?v=1572828150\" alt=\"Stone Exhaust advanced welding techniques\"\u003e\n  \u003c\/p\u003e\n  \u003cp\u003e\n    \u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0284\/6300\/5795\/files\/Stone_Exhaust_Art_of_Welding_-_2_1024x1024.jpg?v=1572828178\" alt=\"Stone Exhaust direct spot welding BMW systems\"\u003e\n  \u003c\/p\u003e\n\n  \u003ch3\u003eWhat our customers say\u003c\/h3\u003e\n  \u003cp\u003eWe have fitted and tested these Stone cat back systems in house and customer feedback has been outstanding. Owners praise the OEM perfect fit, high quality craftsmanship, richer exhaust note and the lack of motorway drone. It is exactly how a BMW F30 328i or F32 428i should sound.\u003c\/p\u003e\n\n  \u003ch3\u003eFitting and installation\u003c\/h3\u003e\n  \u003cp\u003eProfessional fitting is recommended. Nforcd offers expert installation at our Warwickshire workshop. Request a fitting quote at Sales@nforcd.com.\u003c\/p\u003e\n\n  \u003ch3\u003eWarranty\u003c\/h3\u003e\n  \u003cp\u003eStone Exhaust 2 year warranty.\u003c\/p\u003e\n\n  \u003ch3\u003ePopular search terms\u003c\/h3\u003e\n  \u003cp\u003eBMW 328i exhaust, BMW 428i exhaust, BMW F30 exhaust, BMW F32 exhaust, BMW F33 exhaust, BMW F36 exhaust, BMW N20 exhaust, BMW 3 Series 328i cat back, BMW 4 Series 428i cat back, valved catback exhaust BMW, OEM valve exhaust BMW, Stone Exhaust BMW UK, F30 quad exhaust, F32 quad exhaust, BMW 328i performance exhaust, BMW 428i performance exhaust, F30 328i valved exhaust, F32 428i valved exhaust, cat back exhaust UK, BMW exhaust upgrade, BMW N20 cat back, F30 328i dual exit exhaust, F32 428i quad tailpipes.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"Stone Exhaust","offers":[{"title":"OEM Integrated Valve(s) \/ Single Exit (Left) with Twin Tailpipes (Require Original Bumper) \/ Flat Cut Gloss Carbon Fibre (82mm)","offer_id":42565747802300,"sku":null,"price":2396.16,"currency_code":"GBP","in_stock":true},{"title":"OEM Integrated Valve(s) \/ Dual Exit with Single Tailpipe (Require 335i\/435i Bumper) \/ Flat Cut Gloss Carbon Fibre (82mm)","offer_id":42565810782396,"sku":null,"price":2396.16,"currency_code":"GBP","in_stock":true},{"title":"OEM Integrated Valve(s) \/ Dual Exit with Quad Tailpipes (Require M Performance Bumper) \/ Flat Cut Gloss Carbon Fibre (82mm)","offer_id":42565810815164,"sku":null,"price":2835.84,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0552\/9465\/6700\/products\/BMWN20F30F32_Cat-BackValvetronicExhaust2-2_1024x1024_2x_36a12ae2-25cd-4335-b183-d37d9ea4969f.webp?v=1680525233","url":"https:\/\/www.nforcd.com\/products\/stone-exhaust-bmw-n20-f30-f32-cat-back-valvetronic-exhaust-inc-328i-428i-1","provider":"Nforcd","version":"1.0","type":"link"}