Correct me if im wrong but on my 03 STi with PPP i should have a standard down pipe, a prodrive front pipe with sports cat, standard middle with CAT section and prodriver rear silencer?

If thats correct then to unleash a little more noise I should be looking at a decat centre section? The CAT in the front pipe should still keep emissions on the legal side?

Thanks.

 

You are indeed wrong.

Prodrive Sports Cat DP, Prodrive Decat Rear Centre, Subaru Resonated/silenced centre, Prodrive Back Box. Subaru Decat Up-pipe.

Straight through centre, will have no bearing on emissions but will make the exhaust noisier.

Stainless exhausts manifolds headers

Although kind of depends on how much noise you want.

 

Ah ok, so the first CAT is in the downpipe then the a 2nd cat before the resonated centre?

Thus with PPP I am only running the one CAT in the downpipe?

thus doing anyway with the standard centre section will free up some noise, which is my goal as ive been told the prodrive exhaust set up will be good for my tuning aims.

On my old WRX I had a straight through 3" system with no cats and a fire spitting, crackling popping super loud barstad of a system, great fun but never again. Just that my STi is a little too docile in terms of sound, hopefully removing the resonated centre section will be a happy medium.

thanks.

 

Yep just one cat 100 cell Prodrive Sports Cat Down Pipe.

I would start with that then. Also revs a little more freely with the straight through centre, I found it nicer to drive.