Apart from the noise will i gain any performance from a screamer pipe? I was reading on a Porsche build that it's better to run atmosphericly instead of plumbing the gases back into the exhaust to prevent turbulence?

Currently plumbed into the downpipe.

 

I put a screamer pipe on my old civic when i turbo'd it, not a clue if it had any advantages over having it plumbed back to exhaust though as i never had it piped that way.. it was the noise that won it for me every time

 

This is somethin I'm intrested in too friend done it on his evo but bought a ready made manifold how would you do it on a scooby ?

 

on my downpipe on my impreza it has two pipes, the main downpipe bit off the turbo and a smaller pipe which comes off the waste gate which runs down and plumbs into the main pipe about 12" further down. i think most downpipes cover the whole exhaust side of the turbo like a standards one does?? maybe someone can confirm this.... i think mine is a magnex race dowpipe. worth a google to have a look. you could cut it off where it joins the main pipe and have the hole plated to leave a screamer?