Made a quick and dirty video for some bolt in silencers for my z4m, here's a cheeky video for those interested! Not a massive difference on a cold idle test, definitely looses the rasp / snaps / pops, when driving much more evident especially at cruising speeds of 70mph with a noticeable drop in drone levels.
https://youtu.be/neGuObhSPyM
https://youtu.be/neGuObhSPyM