Dinan Free Flow Axle-Back Exhaust - BMW M5 (F90) 2018-2023 - Black Tips

Dinan's Free Flow axle-back exhaust for the F90 M5 enlarges the tubing to 83mm versus the 80mm stock diameter to free up flow, adding 6 horsepower and 5 lb-ft at 6600 RPM. Twin 76mm secondary valves are 30% less restrictive than the OE valves and stay computer controlled, quiet at low speed and open fully under load, with tone still adjustable through the M-Drive settings. The full system is 100% 304 stainless steel and bolts on with the included hardware. It exits through four 4 inch double-walled clamp-on laser engraved black ceramic tips.

Specifications

Documents: Installation Instructions (PDF)

This part fits:

Shipping

• In-stock orders placed before 3 PM EST ship the same day — everything else ships within 24 hours.
• Standard, expedited, and overnight options at checkout.
• Oversized items ship by freight and take longer.
• Backordered items ship as soon as stock lands — contact us for lead times.
• International orders: prices do not include VAT, duties, or import fees. Your country charges these at import and they are the buyer’s responsibility.

Returns

• 30-day returns on new, uninstalled items in original packaging with all hardware.
• Standard returns: 8% restocking fee, buyer pays return shipping. Both waived if the item is defective or we made the error.
• Installed or used parts can’t be returned — confirm fitment before you install.
• Special orders and custom items are final sale.
• Email us for return authorization before shipping anything back.

Full details: Shipping Policy · Refund Policy