Can anyone confirm whether the STI PPP has a centre pipe with a cat or not. I had assumed that a new de-cat centre pipe was the enxt vhange but just heard that the PPP involves the withdrawal of the centre cat pipe?

What can I do to get that distinctive burble out of my exhaust system?

 

First cat in the downpipe, replaced with PPP sports cat.
Second cat in the link pipe or forward center, removed with PPP.
Resonator in the center section, left as standard.

The Prodrive backbox is a bit quiet for some people, although does sound better from outside the car.

Changing center section and removing the resonator will add a bit more volume.

Obviously any mods done to the system could infringe your warranty.