Milltek Sport Cat-Back Exhaust - 2021+ BMW 4 Series G82 M4 & M4 Competition S58 3.0 Turbo

Upgrade the BMW 4 Series G82 M4 & M4 Competition S58 3.0 Turbo (2021+) with a Milltek Sport cat-back exhaust. Milltek builds each system around the car it fits: mandrel-bent T304L stainless pipework, a larger bore than stock for freer flow, and a tuned sound you choose, from quiet and refined to loud and uncorked.

Choose your setup

• Sound: the system type and sound level.
• Tip Finish: the tailpipe trim.
• Optional Downpipe: add a Milltek catted or catless downpipe built to fit this cat-back. Pick Cat-Back Only to skip it.

Cat-back systems: compare every part number

What comes with each cat-back

• SSXBM1169: 2 x Adapters to OE GPF/OPF; 1 x LH Valved Link & Outlet Pipe; 1 x RH Valved Link & Outlet Pipe; 1 x Rear Silencer; 4 x Polished 4.5" Trims; 115 GT Milltek note: Axle Back System with GT-115 Polished Trims - Requires OE system to be cut.
• SSXBM1170: 2 x Adapters to OE GPF/OPF; 1 x LH Valved Link & Outlet Pipe; 1 x RH Valved Link & Outlet Pipe; 1 x Rear Silencer; 4 x Cerakote Black 4.5" Trims; 115 GT Milltek note: Axle Back System with GT-115 Cerakote Black Trims - Requires OE system to be cut.
• SSXBM1171: 2 x Adapters to OE GPF/OPF; 1 x LH Valved Link & Outlet Pipe; 1 x RH Valved Link & Outlet Pipe; 1 x Rear Silencer; 4 x Titanium 4.5" Trims; 115 GT Milltek note: Axle Back System with GT-115 Brushed Titanium Trims - Requires OE system to be cut.
• SSXBM1172: 2 x Adapters to OE GPF/OPF; 1 x LH Valved Link & Outlet Pipe; 1 x RH Valved Link & Outlet Pipe; 1 x Rear Silencer; 4 x Burnt Titanium 4.5" Trims; 115 GT Milltek note: Axle Back System with GT-115 Burnt Titanium Trims - Requires OE system to be cut.
• SSXBM1173: 2 x Adapters to OE GPF/OPF; 1 x LH Valved Link & Outlet Pipe; 1 x RH Valved Link & Outlet Pipe; 1 x Rear Silencer; 4 x Carbon Fibre 4.5" Trims; 115 JET Milltek note: Axle Back System with JET-115 Carbon Trims - Requires OE system to be cut.
• SSXBM1317: 1 x LH Silencer Bypass (to OE GPF); 1 x RH Silencer Bypass (to OE GPF); 1 x LH Valved Link & Outlet Pipe; 1 x RH Valved Link & Outlet Pipe; 1 x Chassis Brace Plate; 1 x Rear Silencer; 4 x Polished 4.5" Trims; 115 GT Milltek note: Secondary Cat Back System with Centre Resonator Bypass & GT-115 Polished Trims - Requires OE system to be cut.
• SSXBM1318: 1 x LH Silencer Bypass (to OE GPF); 1 x RH Silencer Bypass (to OE GPF); 1 x LH Valved Link & Outlet Pipe; 1 x RH Valved Link & Outlet Pipe; 1 x Chassis Brace Plate; 1 x Rear Silencer; 4 x Cerakote Black 4.5" Trims; 115 GT Milltek note: Secondary Cat Back System with Centre Resonator Bypass & GT-115 Cerakote Black Trims - Requires OE system to be cut.
• SSXBM1319: 1 x LH Silencer Bypass (to OE GPF); 1 x RH Silencer Bypass (to OE GPF); 1 x LH Valved Link & Outlet Pipe; 1 x RH Valved Link & Outlet Pipe; 1 x Chassis Brace Plate; 1 x Rear Silencer; 4 x Titanium 4.5" Trims; 115 GT Milltek note: Secondary Cat Back System with Centre Resonator Bypass & GT-115 Brushed Titanium Trims - Requires OE system to be cut.
• SSXBM1321: 1 x LH Silencer Bypass (to OE GPF); 1 x RH Silencer Bypass (to OE GPF); 1 x LH Valved Link & Outlet Pipe; 1 x RH Valved Link & Outlet Pipe; 1 x Chassis Brace Plate; 1 x Rear Silencer; 4 x Carbon Fibre 4.5" Trims; 115 JET Milltek note: Secondary Cat Back System with Centre Resonator Bypass & JET-115 Carbon Fiber Trims - Requires OE system to be cut.
• SSXBM1320: 1 x LH Silencer Bypass (to OE GPF); 1 x RH Silencer Bypass (to OE GPF); 1 x LH Valved Link & Outlet Pipe; 1 x RH Valved Link & Outlet Pipe; 1 x Chassis Brace Plate; 1 x Rear Silencer; 4 x Burnt Titanium 4.5" Trims; 115 GT Milltek note: Secondary Cat Back System with Centre Resonator Bypass & GT-115 Burnt/Blue Titanium Trims - Requires OE system to be cut.

Downpipe options: compare every part number

"Race/Track only" and "Stage 2 ECU remap" are shown only where Milltek states them. A dash means Milltek does not state it for that part.

What comes with each downpipe option

• SSXBM1271: 1 x LH Primary Cat Bypass; 1 x RH Primary Cat Bypass; 1 x LH Cat Link Pipe Milltek note: Requires Stage 2 ECU Remap - Fits to OE and Milltek Sport Systems.
• SSXBM1235: 1 x LH Downpipe & Cat Assembly; 1 x RH Downpipe & Cat Assembly; 1 x LH Cat Link Pipe Milltek note: with HJS HQ 200CPSI Cats (No CEL or ECU Software Required) - Fits to OE Secondary Cats & Milltek Sport Cat Back System.

Catted and catless downpipes

A catted downpipe keeps a catalytic converter in the downpipe. A catless downpipe (de-cat) replaces it with a straight pipe. Each option name above says which one it is.

Fitment

BMW 4 Series G82 M4 & M4 Competition S58 3.0 Turbo, 2021+. US-market model listing. Confirm your exact model, engine and options before ordering, and message us if you are not sure.

About Milltek Sport

• T304L stainless steel, CNC mandrel bent.
• Designed and developed in Derby, UK with a US facility in Knoxville, Tennessee, and tested at the Nürburgring.
• Company founded in 1983.

Warranty

Milltek covers most products with a lifetime guarantee. Downpipes, hi-flow catalysts and any part with valves are covered for 2 years or 80,000 km, and electronic products for 2 years. Claims go through the authorized dealer you bought from, and cover the original purchaser only. Full terms: millteksport.com/Warranty.html

Notes

• Catless downpipes and other cat bypass parts replace emissions equipment. They are sold for off-road and competition use where local law allows. You are responsible for checking the rules that apply to your vehicle.
• Some downpipe options need a Stage 2 ECU remap. Read the option name before you order.
• Fitting times are Milltek estimates for a professional installer.