BMW shipped the G90 M5 without exhaust valves. Active Autowerke put them back. The Signature Valved Catback System transforms how the S68 4.4L twin-turbo V8 sounds and breathes, delivering a deep, aggressive tone on demand without giving up daily drivability.

The system is built from mandrel-bent T304 stainless steel and TIG-welded end to end for durability and corrosion resistance. A high-flow X-pipe midsection sits at the center of the design, balancing exhaust pulses between banks for a fuller, more resonant tone. Piping runs 3.5” (89mm) from the downpipes back, reducing backpressure across the entire system while cutting roughly 10 to 12 lbs versus the OEM setup.

Remote-controlled electronic valves give you full authority over the sound. Quiet and civil in Comfort, fully open and aggressive when you want it. Quad 112mm dual-wall tips finish the system in your choice of four finishes. Paired with catted downpipes, expect an estimated 18 to 22 hp and 20 to 25 lb-ft. Installation is a direct bolt-on with no cutting or welding, and the system is fully reversible to stock.

Key Features

  • Restores the exhaust valves BMW left off the G90 M5
  • Remote-controlled electronic valve system, quiet in Comfort and aggressive when opened
  • Mandrel-bent T304 stainless steel, TIG-welded throughout
  • High-flow X-pipe midsection balances pulses between banks
  • 3.5” (89mm) piping from downpipes to rear exhaust
  • Quad 112mm dual-wall tips in four finishes
  • Approximately 10 to 12 lbs lighter than the OEM system
  • Estimated +18 to 22 hp and +20 to 25 lb-ft when paired with catted downpipes
  • Direct bolt-on installation, no cutting or welding
  • Fully reversible to stock
  • Made in Miami, Florida

Vehicle Fitment

BMW M5 (G90), 2025 and newer, and M5 Touring (G99)