Best Cat-Back Exhaust Systems for BMW 4 G22

When it comes to exhaust upgrades on the BMW G22 4 Series, the options are genuinely exciting, particularly for owners running the B58 straight-six in the M440i. The OEM exhaust is deliberately muted to meet noise regulations, so there's real performance and sound to unlock here. Popular cat-back systems from Remus, Milltek, and Eisenmann are well-regarded choices that offer a noticeable improvement in tone without pushing into drone territory on the motorway. For those wanting to go further, a downpipe upgrade - particularly a high-flow catted unit from brands like AWE Tuning or BM3-compatible suppliers - pairs exceptionally well with an ECU remap to extract meaningful power gains. Valvetronic systems are worth serious consideration on the G22 since they give you daily-driver refinement with the option to open things up when you want it. Practically speaking, always confirm emissions compliance for your region before fitting a decat or sports catalyst, and if you're stacking a downpipe with a tune, use a reputable map writer familiar with the B58 to avoid fuelling issues and protect your drivetrain long-term.