We are proud to introduce you to the state of the art Stone Exhaust Valvetronic Cat-Back Exhaust System with dual valves, to enhance the performance and sound of your BMW G30 Sedan 520i & G31 Touring 520i with the B48 engine.
Stone Exhaust has been developing world's best exhaust system since 1998, starting with 3D scanning and reverse engineering the OEM system, this allows the Stone engineers to design a 100% OEM fitment exhaust with precision. With our in-house dyno, your BMW exhaust system is proven to produce more power with the enhanced Stone signature exhaust sound.
The OEM Integred Valves option allows your exhuast system to operate as standard, where the onboard computer (ECU) will control the opening and closing of the valves automatically.
You may wish to add the Stone Valvetronic System (Dual Valves) which enables you to control the valves remotely via the stone remote controller.
Available to add-on Stone Valvetronic System
Plug and Play OBDII controller
One Piece Design
Mechanical Welding with Precision
In House Research and Development
3D Scanning & Reverse Engineering
Dyno Developed In House
Eliminates drone found on the standard exhaust system
BMW G30 B48 520i STONE EXHAUST Turboback Sound
Stone offers an OPF delete, which can be included free of charge, this allows you to install the Stone Cat-Back exhaust system on OPF equipped cars without throwing an error code, thus coding out the OPF error code on the ECU is not required.
R&D and 3D Scanning
Stone Exhaust engineers use reverse engineering by 3D scanning OEM parts to understand their functionality and identify weaknesses. Data has been collected continuously in order to analyze factors such as pipe diameter, route and degrees of the bending angles of the Exhaust System found on the BMW.
During R&D, Stone Exhaust utilizes the 3D simulation software to stimulate the exhaust gas flow movement, thermal and pressure rise zone. Progressive improvements were continually made until the optimal performance was achieved.
7 Axis CNC Bending Machine
Stone Exhaust System are constructed utilizing a 7 axis CNC Bending Machine which is the ultimate machine for high levels of precision delivery, necessary for industries such as the aerospace and defense industries.
With the state-of-the-art bending machine, Stone Exhaust has achieved the industry’s standard to an impressive 98% roundness, whilst maintaining the wear of the outer bore at only 25% at 180°. Airflow obstruction and welding fracture problems are prevented by utilizing this technology. With the combination of the CNC Bending machine, Reverse Engineering and 3D Design Scanning, Stone exhaust has created an integrally molded exhaust pipe with an accuracy error under 0.025mm.
Crisscross and Overlapping Welding Technique
The flange between the turbo and the downpipes reaches extreme temperatures (800℃ to 1100℃) which creates stress on the connection point. By utilizing both welding techniques to increases the width and penetration of welds. This increases the endurance and tolerance of these connection points, leading to quality products with reliable performance.
Direct Spot Welding
Our highly skilled engineers perform direct spot welding to increase product strength. This is undertaken by mechanical welding arms, proven to achieve greater precision and penetration in their welds compared to manual welding, resulting in an end product that is a work of art.
Compatibility - B48 Engine
BMW 5 Series
G30 520i (2016-2019)
G31 520i (2016-2019)
AP527A (Require Original Bumper)
Stone Exhaust 2Year Warranty
110cm x 33cm x 60cm
Various U.S. states and the U.S. federal government have individual laws regulating the use of aftermarket exhaust parts and system, especially when the stock system is modified, remove, or if you are replacing original catalysts. Please consult the appropriate law department in your area before installing any aftermarket part or system on your vehicle to ensure compliance with all applicable laws. The purchasers are entirely responsible for informing themselves of the applicable laws where the products are to be used and to comply with those laws.
If you are residing in Europe, Stone’s cat-back exhausts are OPF-compatible, which means you won’t need to code out the OPF or worry about losing your warranty.