Supersprint Rear Silencer/Back Box/Backbox/Muffler Axle-Back for BMW 1 Series M135i & M140i F20/F21 (N55/B58) – Stainless Steel Twin Exit 100mm Tailpipes – ECE Approved Road Legal – Performance Rear Section Exhaust Upgrade – Part 988624

Supersprint Rear Silencer with 100 mm Tips for BMW 1 Series M135i and M140i F20 F21 Part No. 988624

Give your M135i or M140i the sound and presence it deserves. This Supersprint rear section replaces the factory back box with a beautifully crafted stainless unit featuring twin 100 mm outlets that fill the OE diffuser perfectly. It is a direct replacement for the standard muffler on N55 and B58 powered cars, offering a richer note on throttle and a refined cruise, all with ECE type approval for road use.

Highlights

• Model specific for BMW 1 Series F20 and F21 M135i N55 and M140i B58 for precise fit and finish
• Dual 100 mm round tailpipes for a bold factory plus look with perfect alignment in the OEM valance
• Even left and right gas flow for a balanced tone and clean aesthetics
• Deletes the stock exhaust flap without warning lights or drivability issues
• No cutting required uses factory hangers and hardware for a simple swap
• ECE approved MOT friendly and road legal no OBD errors
• High grade AISI 304 and 409 stainless steel with premium welds for long term durability
• 36 month warranty with unlimited mileage from Supersprint
• Part number 988624

Sound and quality you will love

Expect a deeper sportier soundtrack without intrusive cabin boom. At motorway speeds it remains civilised yet it comes alive under load with a crisp performance focused character. We have supplied and fitted this system for many customers and feedback has been consistently excellent fitment is spot on finish is first class and the tone is exactly what an M135i or M140i should have.

Finish options

100 mm outlets available on request in matte black polished black or satin silver to suit your styling goals.

Kit and installation notes

To be installed as a kit with 524212 and 988603 or 988613.

Professional fitting available at MJ Modifications in Warwickshire. Request a quote via info@mjmodifications.co.uk.

Compatibility

• BMW 1 Series F20 and F21 M135i N55
• BMW 1 Series F20 and F21 M140i B58

Safety and compliance

Built to meet OE level safety expectations including JASO thermal and fire safety considerations in critical areas. ECE type approved for street use.

Why choose this upgrade

• Back box upgrade that enhances character without drone
• Straight bolt on installation using OE mounts
• Perfect choice if you want a road legal sound upgrade and premium materials

What people are searching for

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