Double Res delete for the M140i is Mental

We get the twin res delete exhaust modification on a b58 M140i. If your considering modding your exhaust for for you BMW and wondered if it was the right thing to do. This may very well answer the age old question. Keep it stock or send it?
335i PE - MOD VIDEO here - studio.youtube...
z3 Muffler delete - • Rear muffler Delete BM...
Solid mechanical and engineering - solidmechanica...