Active Autowerke AFlow Catted Downpipe - BMW B58N M340i / M440i (2025+)

NO PERFORMANCE TUNE NEEDED. Active Autowerke BMW B58N Gen-3 Catted Downpipe - this is for M340 and M440 B58N Gen-3 and the X3 M50 which also incorporates a new GPF into the downpipe. NOTE that to remove the stock GPF downpipe requires 9 to 10 hours of labor as the subframe needs to be dropped. NOTE: Fitment applies to US model cars only unless specifically stated. We cannot guarantee fitment to non-US model cars. BMW introduced a new valvetronic, single turbo version of its direct-injection engine for the later F-Chassis models beginning in 2016 and carried over to the G-chassis models has been updated with the Gen-3 version the B58N. The Active Autowerke B58N Gen-3 downpipe for the B58N helps unleash some of the potential that is restricted by the OEM downpipe. Turbochargers are powered by spent exhaust gases created during the combustion process.

Brand: Active Autowerke

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.
• Free US shipping on orders over $250.
• 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.