Fabspeed HJS Sport Cat Downpipe for BMW B58N

Replace the matching BMW B58N catalyst/downpipe assembly with a stainless Fabspeed downpipe using a German HJS 200-cell core. Match the original assembly reference as well as the engine; a general B58 badge is insufficient. Fabspeed Motorsport, based in Fort Washington, Pennsylvania, develops exhaust systems, air intakes and ECU tuning for sports cars including Porsche. Its development work uses dynamometer testing, road evaluation and racetrack testing.

Before you order

Confirm the engine, production specification and original catalyst reference before ordering. A B58N label or xDrive50e badge alone does not establish the correct downpipe assembly.

Technical Details

• Manufacturer product reference: FS.BMW.B58N.SC.
• Corresponding original assembly reference: 18325A04CB2.
• 4-inch tubing before the catalyst and 3-inch tubing after it.
• HJS tri-metallic 200-cell catalyst.
• CNC mandrel-bent T304L stainless construction.
• No cutting or welding specified for the matched installation.
• Confirm engine revision, sensor positions and vehicle market.
• Other B58 revisions and later applications require a separate reference check.
• Covered by the Fabspeed Lifetime Warranty, subject to its terms and exclusions.

Use restrictions

A sport catalyst is not proof of application-specific road-emissions approval. Confirm the intended installation and applicable requirements before ordering.

PMB Performance brings over 20 years of parts and fitment experience. Send your VIN and photos or references for the component being replaced for help confirming the correct configuration.

Fitment & Compatibility

Use the application details below together with the original component and any existing modifications.