We are proud to introduce the BR Motorsport 3″ catless downpipes for your Mercedes GLC63 M177 4.0 twin turbo engine variant. This 3″ downpipe is the best value modification available. By eliminating the restrictive catalytic converter in the factory downpipe, back pressure is reduced significantly which results in faster spool, an increase in power & a more aggressive exhaust note. This downpipe is a simple to fit upgrade that also allows for stage 2