[Missouri_f30]

2016 Bmw 328i xdrive - Lci - N20
im wanting to straight pipe my f30 im wanting a aggresive, deeper, louder sounding exhaust system whats your suggestion on pipe size or material?

[Luverse]

i'm using straight pipe on my N20, with 4inch to 3 inch downpipe, and 3 inch all the way to muffler with valvetronic.
Using SUS304 stainless steel

here's my car, after installing straight pipe, with stock tune

[mike@x-ph.com]

Neither.

Straight pipe will not give you a deep tone, it will give you a loud and raspy sound with drone on certain RPM.

If you want a deep an aggressive tone without rasp, you need to get a real exhaust system

[CandyRedRC46]

Lol you're not going to put a 4" exhaust on your 328i.