SLN BMW B58 OPF Ceramic Coated Sports Cat Downpipe M240i M340i M440i 540i 640i

The SLN Performance Ceramic Coated Sports Cat Downpipe is a high-performance upgrade for Gen 2 B58 OPF-equipped BMW models. Built from SS304 aircraft-grade stainless steel and finished with a heat-reducing ceramic coating, it delivers improved power, sharper throttle response, quicker turbo spool and a deeper, more aggressive exhaust tone. Ideal for fast-road and tuned B58 setups.

Fitment: B58 OPF Models – M240i, M340i, M440i, 540i, 640i, 740i, 840i, Z4 M40i, Toyota Supra A90/A91

Key Features

High-Flow Sports Catalyst

– Increases power and torque across the rev range
– Faster turbo spool and improved throttle response
– More aggressive exhaust note with stronger turbo presence

Ceramic Thermal Coating

– Reduces engine bay temperatures
– Helps maintain lower intake air temperatures
– Improves long-term durability of surrounding components

Premium SS304 Construction

– Made from aircraft-grade stainless steel
– TIG-welded for strength and longevity
– Designed for reliable performance on tuned engines

Benefits

Upgrading to the SLN Performance ceramic-coated sports cat downpipe unlocks noticeable gains in power, responsiveness and sound. Reduced heat levels and improved exhaust flow result in better performance on both road and track, while maintaining OEM refinement.

Fitment

Suitable for the following B58 OPF/PPF models only:

– BMW G42 M240i xDrive (2021+)
– BMW G20/G21 M340i (2019+)
– BMW G22 M440i (2019+)
– BMW G30/G31 540i (2018+)
– BMW G32 640i (2018+)
– BMW G11/G12 740i (2019+)
– BMW G14/G15/G16 840i (2019+)
– BMW Z4 G29 M40i (2019+)
– Toyota Supra A90 / A91 GR (2019+)

Installation Notes

– For OPF/PPF vehicles only
– Professional installation recommended
– ECU calibration advised for best results
– Not MOT-legal; for off-road/motorsport use only

About SLN Performance

SLN Performance specialises in high-quality, stainless-steel exhaust and induction components engineered for maximum strength, flow and durability. Their products are trusted across the tuning scene for supporting high-boost, high-heat applications on both road and motorsport builds.