[bigdonnyd40]

Just picked up a 60k mile 2018 M550i. This thing is mint and absolutely loaded. Has just about every option I know of. Service history was great as well, so naturally I’m looking to mod it.

So far it’s BM3 stage 1 and xHP + resonator delete w/ xpipe.

I’m getting a bunch of preventative maintenance done (plugs, ZF oil, diff oil, engine oil, filters, etc.). Radiator and coolant was replaced by previous owner just before I bought it.

I want to get downpipes but I hate the smell of catless. Anyone have any luck with high flow catted pipes? As long as it cleans up the smell or is about 80% as clean as stock I’m happy.

[mike@x-ph.com]

use high quality downpipes like the Evolution Racewerks or if you don want a check engine light, you can get the active autowerke

[Bloom_435i]

I have catless downpipes bm3/Xhp. Stock muffler with x-pipe a little smell with 93 but if you run ethonal the smell is way better overall. If windows are closed you smell nothing. Zero drone also with downpipes.