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Redstar Audi B9 S4/S5 Downpipe
Redstar Audi B9 S4/S5 Downpipe
Redstar Audi B9 S4/S5 Downpipe
Redstar Audi B9 S4/S5 Downpipe
Redstar Audi B9 S4/S5 Downpipe
Redstar Audi B9 S4/S5 Downpipe
Redstar Audi B9 S4/S5 Downpipe
Redstar Audi B9 S4/S5 Downpipe
Redstar Audi B9 S4/S5 Downpipe

Redstar Audi B9 S4/S5 Downpipe

Catalyst Type
Catalyst Type: HJS HD 200cpsi 143mm
Heat Shielding
Heat Shielding: Heat Shielded
Need installation?

Pairs well with

Unleash the performance of your 2017+ Audi S4 B9/B9.5 3.0t Turbo and 2017+ Audi S5 B9/B9.5 3.0t Turbo with Redstar performance exhaust downpipes. Developed with an expansive bore and flow-optimised transitions for superior gas velocity and efficiency, these downpipes replace the restrictive factory sections to let the 3.0T breathe freely and respond harder.

By lowering backpressure you will feel quicker turbo spool, sharper throttle response and real gains in usable power, all accompanied by a deeper, more engaging tone. Choose Redstar's OEM-style heat shielding option with a ceramic inner liner to cut radiant exhaust heat by up to 80%, helping control under-bonnet temperatures and supporting turbo life during demanding use.

Built for durability and seamless fitment, every system uses 2.0mm wall 304L stainless steel, is 100% TIG welded and back purged, and integrates with OEM-spec V-band flanges and factory-style brackets for a true bolt-on upgrade. Tailor the package with GESI GEN2 400cpsi catalytic converters rated to support up to 1000hp for smoother flow than stock and refined operation. Precision engineering, robust manufacturing and unmistakable Redstar sound make this the ideal foundation for extracting more from your Audi S4 or S5.

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 and improved flow
  • Faster turbo spool and sharper throttle response
  • Lower under-bonnet temperatures with optional heat shielding to help protect components and support turbo longevity
  • Deeper, more engaging exhaust tone
  • 100% bolt-on installation using factory mounting points

Technical Specifications

  • Highest quality 2.0mm wall 304L stainless steel
  • 100% TIG welded and back purged
  • OEM-spec V-band flanges
  • All brackets and mounts as on OEM unit

Manufacturer fitment

  • 2017+ Audi S4 B9/B9.5 3.0t Turbo
  • 2017+ Audi S5 B9/B9.5 3.0t Turbo

Fits

Audi A4 (B9) Sedan S4 2016-2024
Audi A4 (B9) Wagon S4 2016-2024
Audi A5 (F5) Convertible S5 2017-2024
Audi A5 (F5) Coupe S5 2017-2024
Audi A5 (F5) Sportback S5 2017-2024

Professional fitting is recommended.

Services we specialise in

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Corner-Weight Adjustment

Corner-weight adjustments, also known as balancing or scaling, are essential for any vehicle aiming to achieve optimal performance, handling, and stability. This process involves adjusting the weight distribution across all four wheels, ensuring that each carries an equal part of the car’s total weight. Ideal for racing enthusiasts, track-day heroes, and those who demand precision in their vehicle’s handling, corner-weight adjustments can significantly impact your driving experience.

Wheel Alignments

Wheel alignment is not just about a smoother ride; it’s a vital service that affects your vehicle’s handling, fuel efficiency, and tire lifespan. Misalignment can lead to uneven tire wear, poor fuel economy, and potentially unsafe driving conditions. Regular checks ensure your vehicle performs at its best.

Safety and Spanner Checks

Ensuring your vehicle operates at its best is not just about performance; it's about safety. At Heasmans, our dedicated Safety and Spanner Checks are designed to give you complete peace of mind on the road. With a team of experienced professionals, we provide thorough inspections and necessary adjustments to maintain your vehicle's reliability and performance.

Premium Wheels

When it comes to enhancing your vehicle's performance and aesthetics, the choice of wheels plays a pivotal role. At Heasmans, we understand this better than anyone. That's why we offer an exclusive collection of premium wheels from the world's most renowned brands like Vossen Wheels, HRE Wheels, Novitec Wheels, and Mansory Wheels, among others. Each brand we offer stands as a testament to our commitment to quality, innovation, and design.

Body Styling

We specialize in elevating the aesthetics and functionality of your vehicle through our premium body styling services. Our expert team is passionate about transforming your car into a statement piece that reflects your unique style while ensuring it stands out on the road.