The Dinan Free Flow Axle-Back Exhaust is built from TIG-welded, 100% brushed T304 stainless steel with larger 76mm tubing versus the 70mm stock piping for freer flow, and twin 76mm computer-controlled valves that are about 30% less restrictive than the OE units, opening under load and quieting low-speed driving. It exits through quad 4.5in (114mm) double-walled, black ceramic-coated, laser-engraved tips that use an inverted clamp-neck design to hide the clamp and keep a clean, straight-cut face. Dinan rates gains of +8 HP and +6 lb-ft at 6600 RPM, and the system is about 5 lbs lighter than stock. Installation is bolt-on with the included mounting hardware.
| Type | Free Flow axle-back exhaust (dual-valve) |
| Material | T304 stainless steel, TIG welded, brushed |
| Tips | Quad 4.5in (114mm) double-walled, laser-engraved, inverted clamp-neck |
| Finish | Black ceramic-coated tips |
| Valves | Twin 76mm computer-controlled (30% less restrictive than OE) |
| Piping Diameter | 76mm (vs 70mm stock) |
| Power Gain | +8 HP & +6 lb-ft @ 6600 RPM |
| Part Number | D660-0086-BLK |
Documents: Installation Instructions (PDF)
This part fits:
| Year | Make | Model | Submodel |
|---|---|---|---|
| 2020-2024 | BMW | X3 | M |
| 2020-2022 | BMW | X3 | M Competition |
| 2020-2025 | BMW | X4 | M |
| 2020-2022 | BMW | X4 | M Competition |
Shipping: In-stock orders placed before 3 PM EST ship the same day, and everything else ships within 24 hours. Standard, expedited, and overnight options are available at checkout. Backordered items ship as soon as we get them back in stock. Contact us for lead times. See the full Shipping Policy.
Returns: 30-day returns on new, unused items in original packaging. See the full Refund Policy.
