Unleash performance from your BMW G80 G81 M3, G82 G83 M4, G87 M2 and Alpina B3/B3 GT G20 G21 with the S58 by fitting Redstar performance exhaust downpipes. Purpose-built for 2020+ M3 and M4, 2023+ M2, and 2025+ LCI Competition variants, these downpipes replace the restrictive factory sections to free the turbos and let the S58 breathe.

A flow-optimised, smooth-transition design reduces backpressure to deliver significant power gains, quicker spool, and sharper throttle response. Optional OEM-style heat shielding reduces radiant exhaust heat by up to 80% to help manage under-bonnet temperatures. Choose high-flow catted configurations with HJS HD 200cpsi metal cores or GESI GEN2 400cpsi converters, both designed to improve exhaust flow compared with stock while maintaining robust operation on the S58 platform.

Every Redstar downpipe is 100% hand made from 2.0mm wall 304L stainless steel with OEM-spec 304L flanges, then TIG welded and back purged for strength and consistency. Designed as a true bolt-on with all OEM-style brackets and LHD/RHD compatibility, the system elevates the exhaust note while supporting turbo longevity through freer flow. Redstar delivers precision engineering, durability, and the unmistakable quality enthusiasts expect from a leading performance exhaust specialist.

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.

Key Performance Benefits

• Significant power gain
• Faster spool and improved throttle response
• Lower under-bonnet temperatures for better component protection
• Richer, more engaging exhaust tone
• Direct bolt-on installation using factory-style mounting points
• Reduced backpressure to support turbocharger longevity

Technical Specifications

• Highest quality 2.0mm wall 304L stainless steel construction
• 100% TIG welded and back purged
• 100% hand made
• OEM-spec 304L stainless steel flanges
• Flow-optimised smooth transition design
• All brackets and mounts as on OEM unit
• LHD/RHD compliant

Fitments

• 2020+ BMW M3 G80 G81 / M4 G82 G83 With S58 Motor
• 2025+ BMW M3 / M4 LCI Competition
• 2020+ Alpina B3 / B3 GT G20 G21 With S58 Motor
• 2023+ BMW M2 G87 With S58 Motor
• 2025+ BMW M2 LCI