Product Specifications
BMW N63B44 4.4L Twin-Turbo Catless Downpipe Set for X5, X6, 550i & 750i xDrive
Looking for a X5 downpipe set for your BMW X5 xDrive50i? This Flashark pair replaces both factory catalytic downpipes on the original N63B44 4.4L twin-turbo V8, with left- and right-side pipes for the twin-turbo exhaust layout. Applications include the 2011–2013 X5 xDrive50i E70, 2008–2014 X6 xDrive50i E71, 2011–2013 550i Base F10 and 2009–2012 750i xDrive F01 listed below.
The larger stainless-steel exhaust path is designed to reduce exhaust restriction after both turbochargers, support quicker turbo response and produce a deeper, more aggressive exhaust note. Match your vehicle’s year, trim, chassis and original N63B44 engine before ordering.
Specifications
| Specification | Details |
|---|---|
| Product Type | Dual catless downpipe set |
| SKU | FLES08347 |
| Engine Application | BMW N63B44 4.4L twin-turbo V8 |
| Turbo-Side Inlet Diameter | 3 inches |
| Outlet Diameter | 2.5 inches |
| Material | Stainless steel |
| Tube Bends | Mandrel-bent |
| Welding | TIG-welded |
| Catalytic Converters | Not included / catless |
Key Features
- Complete Dual-Downpipe Set: Includes one left-side and one right-side downpipe for the N63 twin-turbo layout.
- Turbo-Side Inlets: Designed to create a larger exhaust path after the turbochargers.
- Downstream Outlets: Designed to connect the downpipes to the compatible downstream exhaust configuration.
- Catless Configuration: Removes the restrictive catalytic-converter section for maximum exhaust flow in permitted competition applications.
- Stainless-Steel Construction: Designed to withstand the heat and operating conditions of a twin-turbo exhaust system.
- Mandrel-Bent Tubing: Helps maintain a smoother internal exhaust path through the pipe bends.
- TIG-Welded Connections: Reinforced joints help provide strength and reliable exhaust sealing.
- Integrated Flex Sections: Help absorb normal engine and exhaust-system movement.
- Oxygen-Sensor Ports: Sensor mounting locations are incorporated into both downpipes.
What to Expect
- Reduced exhaust restriction after both turbochargers
- Potentially quicker turbo response
- Deeper and louder exhaust sound
- Improved support for compatible ECU and exhaust upgrades
Performance Notice: Actual results depend on the vehicle’s condition, ECU calibration, turbochargers, exhaust system and other modifications. A specific horsepower or torque increase is not guaranteed.
What Is Included
- 1 × Left-side catless downpipe
- 1 × Right-side catless downpipe
- Exhaust gaskets
- Mounting bolts and hardware shown in the product images
Check Before Ordering
- Verify the year, model, trim, chassis and original N63B44 engine code. BMW used several different 4.4L twin-turbo V8 engines during these model years.
- Do not order for BMW X5 M or X6 M vehicles equipped with the S63 engine, or for N63TU, N63TU2, S63, diesel, naturally aspirated or non-4.4L applications.
- For a 2014 BMW 550i with the updated N63TU engine or a 2014 BMW X5 F15 with the updated N63 engine, do not order unless compatibility has been separately confirmed.
- For BMW X6 ActiveHybrid, BMW 650i or Alpina B7 applications, contact Flashark with the VIN, exact year and chassis before ordering; physical compatibility must be separately confirmed.
- Compare all flanges, sensor locations and outlet connections with the existing exhaust system before beginning installation. Do not install or modify the parts if the connections do not match the vehicle.
- Professional installation is strongly recommended due to limited access around the N63 turbochargers.
- A catless exhaust setup may trigger a check-engine light or emissions-related fault codes. An appropriate ECU calibration may be recommended depending on the vehicle and intended application.
- This product removes the factory catalytic converters. It is not intended for use on pollution-controlled vehicles operated on public roads. Purchase and installation are subject to applicable federal, state and local emissions laws.
Shipping & Returns
Free U.S. Shipping: Orders are typically processed within 1–2 business days and delivered within 7–9 business days. Additional charges may apply to remote areas.
30-Day Returns: Unopened and unused items in their original packaging may be returned within 30 days of receipt. Return shipping is covered for verified quality issues.
Worry-Free Delivery: Optional protection against eligible loss, theft, delay, or transit damage is available at checkout.
