Milltek Sport Secondary Cat-Back Rear Exhaust for BMW 135i 1 Series (E82 Coupe, E88 Convertible) N55 3.0 Turbo, 2010-On – T304/304 Stainless Performance Catback – Sports Rear Section, Back Box/Muffler/Rear Silencer Upgrade – UK Made

British-crafted rear exhaust upgrade for BMW 135i E82 and E88 with the N55 turbocharged 3.0 straight-six

Give your 1 Series 135i a stronger voice and freer breathing with this Milltek Sport rear section that runs from the secondary catalyst rearwards. Built in Britain from premium T304 non-magnetic stainless steel, it delivers a clean, engaging tone on throttle with no intrusive cabin boom on a cruise. This is a direct performance-focused replacement for the factory rear assembly, created for fast road use and everyday drivability.

What makes it stand out

• T304 stainless throughout for outstanding corrosion resistance and long-term durability
• Full mandrel-formed tubing with a larger-than-OE diameter for smoother flow and sharper response
• Carefully tuned silencers for a refined sports soundtrack without motorway drone
• Precision build quality for consistent fit and finish
• Designed specifically for the twin-scroll N55 3.0 petrol turbo platform

Real-world benefits

• Stronger, more characterful exhaust note while remaining civilised day to day
• High quality materials and construction suitable for both standard and lightly tuned cars
• Great baseline for future enhancements such as remaps and intake upgrades
• UK engineering and craftsmanship you can trust

Fitment

• BMW 1 Series 135i Coupé E82 with N55 engine, 2010 onwards
• BMW 1 Series 135i Convertible E88 with N55 engine, 2010 onwards

Our experience

We have run this system on our own builds and supplied it to many customers. Feedback is consistently positive for its quality, refined volume and spot-on sports tone. If you want a durable, British-made exhaust that looks right, sounds right and fits properly, this is the one.

Professional installation

We recommend expert fitting. Book with MJ Modifications in Warwickshire and request a quote at info@mjmodifications.co.uk.

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