I guess I had a little easier time. I just went in to have the head pipes slightly altered to bolt up to my V8 manifolds and shop manager who is a mercedes fan said "you should get rid of these, it's worth 10hp", so I said fine, cut them out. He went on to say that it was legal if they had to be removed because of road damage. So My story is my lowered car bashed them on a speed bump He went on to say that eventually they would fail and start to rattle and that was an expensive repair. Has anyone ever checked to see if there is a power gain?