Originally Posted by CHITOWN1series
I have never seen electric cutouts for a 135i. Do you know of any...possibly a video. And I love my exhaust, its just I have always had loud cars and the eisenmann just isnt loud enough. I'm a young person, and I need to have something a little more obnoxious. I know how horrible that sounds but I just need something louder. I'm just playing with the idea at this point of swapping
This thread was running for some time over at N54tech. It started out being for a 135 but Byoung8 jumped in with his 335i and had some good success.
I really like the product that Byoung8 chose to use (photos on page 5)
Another option might be the RPI quad? I am not sure how much it differs from your setup but I have been very happy with mine! This would let you keep your diffuser (I think).
Here are a couple vids that I had put together. Hope it helps man!