BMW 750i 850i X5 X6 X7 N63R/N63B 3" CATLESS DOWNPIPES

ARM's N63R/N63B downpipes unlock the 4.4L twin-turbo V8 across the full G-Series lineup — 750i, 850i, X5, X6 and X7. Built from full 304 stainless steel in a 3" design, they free a huge sound from the V8 even on the stock exhaust. Removing the OEM converters drops back-pressure and lets the turbos spool faster, adding power and torque throughout the rev range.

Highlights

• Improved turbo spool
• Enhanced exhaust note
• Fully reversible

Construction

BMW fits these V8s into a very compact bay, but the factory downpipe routing already flows smoothly, so we mirrored that path with small refinements for better airflow and easier installation. The downpipes mount to the turbos and midpipes with the same precision as factory. A flex section relieves stress between the upper and lower portion of each downpipe, and a lower bracket below the flex joint secures to the transmission housing — the same anchor point BMW engineered — for a strong, lasting connection. Two O2 sensor bungs per downpipe let you reinstall the oxygen sensors in their factory positions so the DME keeps reading correct fuel-mixture data.

In the box

• ARM G-Series 3" Catless Downpipes
• ARM crush brackets
• Hardware kit

Fitment

Backed by ARM Motorsports' lifetime warranty against defects in craftsmanship and fitment.

Emissions disclaimer: This product is not legal for sale or use on pollution-controlled vehicles operated on public roads and is intended for off-road, race, or closed-course competition use only. You are responsible for compliance with all applicable emissions laws; use on public roads may violate the Federal Clean Air Act (42 U.S.C. § 7522) and similar state laws. Please check your local laws before purchase and installation.

Ships from our Vancouver shop — KORE SPEED is proudly Canadian-owned, with no surprise cross-border duties for Canadian buyers. Questions on fitment? Email support@korespeed.com.