The other day I was servicing a friends 04. after removing the air intake tubing and getting to the oil filter. I noticed what appears to be a baffel in a peice of 5" plastic pipe. His silencer ring fell off with a little help from my screwdriver. the turbo is still very quiet. you think if I lost that piece of 5" baffel pipe and installed 5" pipe in its place it would sing a little more? just a thought. we ordered his BHAF. straight pipe is next if he trusts me with a hack saw and welder.

 

I dunno if they changed it for 2004, but they have a length of straight pipe on the 2003 that has supports built into it to keep the straight section from collapsing from the vacuum of the turbo. It this what you are talking about?

Chris

 

What you are seeing is straightening vanes that serve to lessen turbulent air at the turbo inlet. Some people call it the torque tube.
To remove it would make the turbo less efficient.

 

genos sells an eliminator pipe for that piece [assuming it is the same between the 03-04.0 engines] and on them it is like 5.5", so if you can find some 5" abs pipe it'll work, but 5" exhaust pipe won't [the abs is 5" ID, exhaust pipe is 5" OD]