Looks like Dave has left the building, havent seen a post from him in ages. At any rate, seeing as no one has answered your thread, I would NOT advise moving cam sprockets in the attempt to gain performance. You're assuming that they're not properly setup (timed) from the factory and that's simply not the case. I have yet to see where anyone has done that on a Volvo for performance (yes, I know some cars electronically adjust cam timing for performance). Volvo does it for emissions, not for performance (yet). I highly doubt that you'll find any dealer tech willing to play with your cam timing as it'd be a warranty issue, no one would pay for it (unless you would) and if there's any problems afterwords, technically it could be regarded as being the techs fault (a "comeback").