sound deadening cube material.

[180sx Dreams]

Hi guys, I was actually just wondering about the materials inside hi performance exhausts. I always hear and see these "active composite/ sound deadening" cubes. I'm not questioning whether or not they work, because I'm sure they do, but exactly what are these cubes made of?

[uprev]

Generally they are just rubber damping weights. They don't specifically need to be cube shaped, it's just an efficient size.

They reduce the "ring" of the metal so that you don't get lots of in cab noise. Not exactly applicable to aftermarket loud exhausts.