Transform the exhaust performance of your Mercedes A45 AMG W176, CLA45 AMG W176 and GLA45 AMG X156, each powered by the 2.0L 4cyl M133 engine, with Redstar Exhaust M133 Downpipes. Designed as a direct replacement for the restrictive factory sections, these precision-built downpipes feature a long 3.5in OD primary section that transitions smoothly to 3in OD for optimised flow.
By lowering backpressure, the system delivers significant power gains, faster turbo spool and crisper throttle response, while the optional OEM-style heat shielding with a ceramic inner liner cuts radiant under-bonnet heat by up to 80%. Reduced heat helps protect surrounding components and supports turbocharger longevity, with a richer, more engaging exhaust tone to match.
Manufactured from 2.0mm wall 304 stainless steel, 100% TIG welded and back purged, and finished with OEM-spec bottom ball flanges and factory-style brackets, Redstar downpipes install as a true bolt-on upgrade. Choose between GESI GEN2 400cpsi or HJS 200cpsi ultra high-performance catalytic converters to suit your goals, and experience Redstar performance exhaust engineering built for durability, fitment and results.
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
- Noticeable increase in power and torque from reduced exhaust restriction
- Quicker turbo spool and sharper throttle response
- Lower under-bonnet temperatures that help protect components and support turbo longevity
- Deeper, more engaging exhaust tone
- Straightforward 100% bolt-on installation using factory mounting points
Technical Specifications
- Long 3.5in OD section with smooth transition to 3in OD
- Highest quality 2.0mm wall 304 stainless steel construction
- 100% TIG welded and back purged for strength and consistency
- OEM-spec bottom ball flanges for reliable sealing
- Brackets and mounts mirror the OEM unit for precise fitment
