Redstar Audi B9 RS5|RS4 Downpipes

Description

Transform your Audi RS5 F5 or RS4 8W B9/B9.5 2.9 TFSI with Redstar performance exhaust downpipes engineered for the Porsche 2.9L application. Purpose-built for these platforms, the system focuses on flow efficiency and precision fitment to elevate everyday drivability and track-ready response.

A big bore layout with smooth transitions maximises gas velocity, using long cones to taper the OEM 127mm turbo outlet flanges to an 89mm main section before a second, controlled transition to 76mm. This geometry helps reduce backpressure, sharpen throttle response and improve spool characteristics, delivering meaningful power gains and a richer, more engaging exhaust note.

Manufactured from premium materials and finished to a high standard, each Redstar downpipe integrates with OEM mounting points for a true bolt-on experience and is compliant for both LHD and RHD vehicles. Optional OEM-style heat shielding reduces radiant heat by up to 80% to help protect surrounding components. Designed, built and welded to Redstar’s exacting standards, this is a robust performance upgrade that enhances the character and capability of your Audi RS5 or RS4.

Available Options

• 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.

Key Performance Benefits

• Noticeable power and torque gains from reduced backpressure
• Faster turbo spool with crisper throttle response
• Lower under-bonnet temperatures that help protect nearby components
• Enhanced exhaust tone for a more engaging sound
• Bolt-on installation using factory mounting locations
• Helps promote longer turbocharger service life

Technical Specifications

• Big bore design with smooth transition geometry for efficient flow
• Long cones reduce OEM 127mm turbo flanges to 89mm main diameter, with a second transition to 76mm
• 2.0mm wall 304L stainless steel construction
• 100% TIG welded and back purged
• OEM-spec V-band flanges
• All brackets and mounts mirror the OEM layout
• LHD/RHD compliant

Fitment

• 2018+ Audi RS4 8W B9/B9.5 2.9 TFSI
• 2018+ Audi RS5 F5 2.9 TFSI