Transform your BMW M550i, M650i, M750i xDrive G30, X5 F15 50i, X6 F16 50i, M850i G15 G16 and Alpina B6/B7/B8 with the N63B44 engine using Redstar performance exhaust downpipes. Engineered to mate cleanly with the factory system, each assembly features a smooth transition from a 3.5in OD section to the OEM exhaust for seamless integration and optimised flow.

Unlock a huge increase in exhaust flow that translates into a significant power gain, faster spool up and sharper throttle response, complemented by a richer, more engaging exhaust tone. For thermal control, the optional OEM-style heat shielding reduces radiant exhaust heat by up to 80%, helping curb under bonnet temperatures and supporting turbo longevity.

Built for durability and precision, every Redstar downpipe is 100% TIG welded and back purged from 2.0 mm wall 304 stainless steel, using OEM-spec V-band flanges along with brackets and mounts that replicate the factory layout. Designed as a true 100% bolt-on upgrade, this Redstar downpipe system delivers the performance, quality and fitment discerning owners expect from a premium performance exhaust.

Available Options

• HJS HD 200cpsi Catalytic Converters: Engineered in Germany and trusted worldwide, the HJS 200cpsi ultra high-performance cats are rated for over 1000hp. Renowned for exceptional flow, durability, and consistent quality, these converters set the benchmark for high-output applications. Ideal for drivers demanding maximum performance without compromise.
• GESI GEN2 400cpsi Catalytic Converters: The latest GEN2 series from GESI is rated to support up to 1000hp while offering smoother exhaust flow and improved efficiency compared with factory units. Featuring advanced emissions technology for optimal catalyst function at high flow rates. A strong choice for those seeking significant performance gains with refined operation.
• OEM-Style Heat Shielding: Redstar's signature thermal management system reduces radiant exhaust heat by up to 80%. Developed with motorsport-inspired materials and construction, it uses a multi-layer design of ceramic insulation and embossed stainless steel foil. Unlike wraps or coatings that degrade quickly, Redstar shielding delivers long-term durability and consistent protection for engine bay components.
• Competition/Catless: Maximum flow design for uncompromised performance. Delivers the most aggressive exhaust note and optimal power gains. Track use only - not for road use.

Key Performance Benefits

• Significant power and torque gains from increased exhaust flow
• Faster turbo spool and crisper throttle response
• Reduced under bonnet temperatures for improved component protection
• Deeper, more engaging exhaust sound
• True bolt-on installation that integrates with the OEM system

Technical Specifications

• Smooth transition from a 3.5in OD section to the OEM exhaust connection
• 2.0 mm wall 304 stainless steel construction
• 100% TIG welded and back purged
• OEM-spec V-band flanges
• Brackets and mounts replicate OEM geometry

Notes

• EURO 6 Compliant when configured with HJS HD 200cpsi catalytic converters

Fitments

• 2013+ M550i M650i M750i xDrive G30 N63B44
• 2013+ X5 F15 50i; X6 F16 50i N63B44
• 2019+ M850i G15 G16 N63B44
• 2013+ Alpina B6/B7/B8 N63B44