Whats all this power valve/valvetronic business?
Hey Rich, My (Very) basic understanding of the Powervalve system (which I decided on buying having heard it first person), is that at lower revs the valve is closed and helps keep low down torque, it also helps keep it very quiet for pootling around town, but when you hit boost the valve opens up and bypasses thus making it more free flowing and more sporty sounding (louder, but not excessively so!), its exactly what I wanted after a test drive in the demo car, quiet for pootling round town so as not to upset the local bed wetters (Old people) and when I am on open road nice and sporty sounding.
I am sure Nige can give you full details if you PM or call him, alternatively if your anywhere remotely near Norfolk you can have a listen yourself once its fitted