Fabspeed BMW B58N Sport Catalytic Converter Downpipe (2023+)

The 2023-and-later B58 leaves the factory with a long 12-inch, 700-cell ceramic catalytic converter. That cat chokes exhaust flow, holds back the sound and costs performance. Fabspeed's downpipe replaces it with a larger, higher-flowing converter that still keeps the car clean and free of check engine lights.

What you get

• German-made HJS converters, 200-cell, Euro 6 compliant, with a trimetallic coating.
• 4" piping from the turbo to the cat, then 3" tubing from the cat back to the rest of the exhaust.
• More catalyst surface area, which lets more exhaust through while still cleaning it properly.
• No check engine light, per Fabspeed.
• Direct bolt-on in place of the factory catalytic converter.

Brand: Fabspeed · Part #: FS.BMW.B58N.SC

For off-road / competition use only. Not legal for use on public roads in the United States, including California.

• Ships from the brand or distributor, usually in 3–7 business days.
• Shipping is charged at the carrier's rate, shown at checkout. Orders over 70 lb ship by freight for a flat $99.
• Unused parts can be returned within 30 days. Some items are marked no-refund in their description.

Full details are on our shipping and returns page.