this is true!

, sorry didnt copy n paste the whole comment,
There are a variety of ways to install a catch can. There's one right way, two sort-of right ways, and some would argue that at least one common installation method which is wrong.
Sort of right ways:
1) Disconnect the hose which runs between the PCV valve and the turbo inlet pipe. Run a line from the PCV to the catch can, and another line from the catch can to the turbo inlet hose.
2) Disconnect the hose running between the crank case breather lines and the turbo inlet pipe. Run new hose between the breather line and the catch can and another hose between the can and the inlet pipe.
Right way:
Use two catch cans. Configure one as discussed in option one and the other as described in option 2. For optimal effectiveness, this is the way to go.
Wrong way:
Disconnect the PCV<->Inlet line as well as the Crank Vent<->Inlet line. "T" the PCV and Crank vent lines together, and run the remaining end of the "T" to a single nipple on the inlet pipe. Cap the remaining nipple on the inlet. You'll be sending boost into places that definitely shouldn't ever see any. Bad idea.
taken from nasioc, im sure someone could figure it out.
this was a comment from vlietsti's question in the "meets" section so i figured id move it on ova.
way to tattletell dip.......lol