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.
| Type | Free Flow axle-back exhaust |
| Material | 100% 304 stainless steel |
| Piping | 83mm (vs 80mm stock) |
| Tips | Quad 4" double-walled clamp-on, laser engraved |
| Tip Finish | Black ceramic coated |
| Valves | Twin 76mm secondary, 30% less restrictive than OE |
| Power Gain | +6 HP, +5 lb-ft @ 6600 RPM |
| Part Number | D660-0079-BLK |
Documents: Installation Instructions (PDF)
This part fits:
| Year | Make | Model | Submodel |
|---|---|---|---|
| 2018-2023 | BMW | M5 | Base |
| 2019-2021 | BMW | M5 | Competition |
| 2022 | BMW | M5 | CS |
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Returns: 30-day returns on new, unused items in original packaging. See the full Refund Policy.
