I have a 2009 328i, a friend gave me a 2012 m4 exhaust system, can it be installed or modify into the 328i, its from cat back !!!!
Put it up on a lift and compare the M4 exhaust to the vehicle you have. I would guess it won't fit, but you will never know without looking.
Any good exhaust shop can modify it to fit your vehicle, just as long as they don't have to touch the catalytic converter.
Looking for a Used 3 Series in your area?
CarGurus has 39,936 nationwide 3 Series listings starting at $1,500.
Search BMW 3 Series Questions
BMW 3 Series Experts