Originally Posted by bcl0328
they sound similar.
They don't in the real world, my car is N55 powered and we also have an N20 powered 328i. The 328i doesn't sound bad, but it's not a very exciting sound and you can barely even hear it.
The N55 on the other hand is pure music, very angry music especially after you open up the exhaust flap (both of our cars have the flap always open but it barely makes a difference on the 328i, on my 135i it actually bypasses the muffler)