The MagnaFlow SPEQ Series #19828 cat-back exhaust is engineered for BMW G20, G22, and G23 M340i/M440i and xDrive models equipped with the 3.0L B58 inline-6. Designed to improve exhaust flow, amplify performance sound, and enhance visual appeal, it aggressively elevates the character of modern BMW performance. Constructed from mandrel bent 3” 304 stainless steel tubing with a 3.5” front pipe, it offers excellent durability and corrosion resistance. A stamped Y-pipe smoothly merges exhaust pulses for improved efficiency, while the straight-through design is dyno proven to support power gains for both stock and high output applications. Sound is managed through dual 5x8” straight-through mufflers and an NDT resonator, producing a deep, aggressive performance tone under acceleration while eliminating drone at cruising speeds. The result is a strong, assertive exhaust note that stays controlled in daily driving and opens up with pops and cracks when you get on or off the throttle. The system features interchangeable tip options secured with racing bred V-band clamps for a leak free, heat stable connection. Choose quad 3.5” black chrome tips with laser etched MagnaFlow “MF” logos or reuse factory tips. OEM valve functionality is retained by MagnaFlow’s cast stainless valves, allowing full integration with all driving modes. Designed as a direct replacement for factory components behind the catalytic converters, the system includes band clamps, laser cut logo brackets, and all necessary installation hardware for a secure, precise fit, achieved through 3D scanning and CNC robotic manufacturing ensuring a true direct-fit installation. Backed by MagnaFlow’s limited lifetime construction warranty, this cat-back delivers a measurable upgrade in sound quality, flow efficiency, and overall power. Designed with a focus on real world performance, it enhances the B58 with a power focused exhaust tone and the premium construction demanded by modern high output performance.
This Part Fits:
| Year |
Make |
Model |
Submodel |
| 2020-2024 |
BMW |
M340i |
Base |
| 2020-2024 |
BMW |
M340i xDrive |
Base |
| 2021-2024 |
BMW |
M440i |
Base |
| 2021-2024 |
BMW |
M440i xDrive |
Base |
