Milltek SSXBM1128 Race Downpipes - Decat/Catless Front Pipes, OPF/GPF Bypass Delete, Straight Pipes for BMW M4 F82 F83 M4 Competition (2019-2020 OPF) S55 F8x Stage 2 Coupe & Convertible - Track Use Only

Milltek SSXBM1128 Race Downpipes with particulate filter bypass for BMW M4 F82 F83 and M4 Competition, OPF models 2019 to 2020

Unlock your S55 twin turbo with Milltek’s catless front pipes and filter bypass solution. Part number SSXBM1128 replaces the restrictive OPF hardware on late F8x M4 and frees up exhaust flow for faster spool, reduced backpressure and a raw, motorsport soundtrack. If you want a serious track-only exhaust upgrade that transforms response and character, this is the hardware the M community asks for.

Made in the UK from premium T304 stainless steel and hand finished, these large diameter pipes use precision mandrel bends to maintain smooth, constant radius transitions for optimal gas velocity. The result is a crisper, harder edged tone with Milltek’s hallmark acoustic refinement, developed to keep unpleasant cabin boom at bay while delivering that aggressive race-car vibe outside.

Why this S55 downpipe upgrade

• Big diameter straight-through design for meaningful flow gains and lower turbine backpressure
• T304 non-magnetic stainless steel, corrosion resistant and built to last
• UK fabricated and hand finished for consistent quality
• Sharpened throttle response and freer revving feel on track
• Purpose built for OPF-equipped F82 and F83, including Competition variants
• Ideal hardware for Stage 2 style tuning packages and performance remaps
• Pairs perfectly with Milltek cat-back systems and other performance exhaust components

Fitment

• BMW M4 F82 Coupe, OPF models, 2019 to 2020
• BMW M4 F83 Convertible, OPF models, 2019 to 2020
• BMW M4 Competition, OPF models, 2019 to 2020
• Engine code: S55 twin turbo
• Milltek part number: SSXBM1128

What you will notice

• Harder, motorsport-inspired note with pronounced turbo presence and crackle under load
• Improved turbo response thanks to reduced restriction
• A stronger, more engaging driving experience on circuit and during track days

Real-world feedback

We have fitted SSXBM1128 on customer M4s and the response has been outstanding. Owners report a livelier feel, faster pick-up and a sound that finally lets the S55 breathe. This is a favourite with track-focused builds looking for the ultimate OPF and catalyst delete solution.

Important information

• For off-road and motorsport use only where removal of emissions equipment is permitted
• Professional installation recommended

Fitting and enquiries

Want it installed by specialists who know F8x inside out? Book your fitting with MJ Modifications in Warwickshire. Request a quote at info@mjmodifications.co.uk.

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