Ok doing it just to pull out some fiberglass and then plugging the hole doesn't sound like as bad of an idea. As long as you plug the hole i would imagine it would give a more aggressive sound fo free! I wouldn't do it but I am curious to what it ends up sounding like.....Probably not too bad
The hole should be made anywhere flat so the plug (a sink hole cover) fits better.
I took out three quarters of the insides. (as well as I could estimate) This results in a significantly better bass note especially at idle and low rpm, but did not make the car louder. At higher rpms I do not notice a difference from stock. My guess is that taking out more of the stuffing would not make a difference.
I'm pretty sure it gave me at least 20-30 extra hp as well.:lol:
I had to drill two holes to get it all out. Once a strand is started it just comes out in a stream of fiberglass. I wore old leather dress gloves and just needle nose pliers to help with the knots pulling up in a circular motion. I could get about half of the material out then had to drill a second hole. I tried drilling a hole on the side but still had to drill a second one anyway. I tried drilling a pair of holes on the bottom but there was nothing there...now I have 6 holes to plug. It will be awhile before I get some audio.
Just a question. Why not some cuts outs? You can cap them for quiet and open them for loud. You are looking at about 100 bucks. Just do it after the cats your car won't know the difference.
I have used them before. You can even get the electric ones and open and close them from the drives seat.