ARM Motorsports Catless Downpipes
G30 M550i · G11 750i · G14 · G15 · G16 M850i · G05 X5 · G06 X6 · G07 X7 | 4.4L Turbo V8 [N63]

ARM Motorsports' N63R/N63B downpipes for the 4.4L V8 Twin-Turbo powered G-Series allows you to take your BMW to the next level. Made with full 304 Stainless Steel and 3" construction these downpipes open up an incredible sound from the twin turbocharged V8 even with the stock exhaust! By replacing the OEM downpipes with the ARM G-Series Catless Downpipes, you'll be removing the restriction from the OEM converters which will reduce exhaust back-pressure and allow the exhaust from the turbochargers to flow more freely. This increase in exhaust flow allows for the turbos to spool faster, increasing power and torque throughout the RPM range of your BMW.

As with all BMW's, everything is designed to fit in a very compact space, and the G-Series downpipes are no exception. However, BMW did an excellent job of engineering the downpipes to flow in the smoothest path from the turbocharges down to the mid pipe section. Our downpipes essentially followed the same exhaust flow path with a few small modifications to make airflow smoother and installation easier. Consequently, the ARM N63R downpipes mount up to the turbos and midpipes with the same precision as you would expect from the factory N63R/N63B downpipes.

The ARM G-Series downpipes come with a flex section to relieve stress between the upper and lower portion of the downpipe. To further reduce any tension on the turbochargers, we have developed a lower bracket on the lower portion below the flex joint where it is secured to the transmission housing. These are the same points BMW designed their factory M550i downpipes to be secured, which means a strong and lasting connection safe for all of the components on the vehicle.

The ARM G-Series downpipes utilize two O2 sensor bungs on each downpipe to allow for reinstalling the O2 sensors in their factory locations. This allows the correct oxygen sensor data to be sent to the DME. This is essential for the DME to properly monitor the fuel mixture in the exhaust gas that are critical to having your M550i motor running smoothly.

Features:

• Improved Turbo Spool
• Enhanced Exhaust Note
• Fully Reversible
• 304 Stainless Steel construction

What's Included:

• ARM Motorsports Catless Downpipes
• ARM Crush Brackets
• Hardware Kit