V70R AWD help!

[Dab of oppo]

Hi guys, a good friend of mine has a Saffron coloured V70R AWD, I have first dibs on it when he sells it (in the next few months he reckons)
He has it serviced at Volvo at the recommended intervals etc, and whilst he loves it he doesn't know alot about it...
He is the second owner, the first one seems to have spent money on the car tuning wise, I'm just wondering if it has been spent well!
The car seems to have a Volvo strut brace on (I believe this is standard fit) It also has black hard piping for the turbo (Standard fit???) Blue samco hose kit (Aftermarket) HKS mushroom filter (Aftermarket) as well as this the car seems to have a double 3" (one each side) exhaust system that sounds lovely...
and then two puzzlers, running along intake manifold there seems to be some form of filter about 1" in diameter and 8" long spliced into the fuel line (???) which I havn't got a clue about what it does, the other is in the glove box there is a blue cable that apparently used to be connected to a box with some form of switch which changed the tune of the engine - this has been unplugged but the box has been misplaced (hope he finds the bugger!) it was removed as his wife found the car a bit too frantic!

I know the descriptions may not be of any use but its worth a shot as google and the forums have prooved fruitless for me!

[Dab of oppo]

Thanks guys, the filter I described is not an air filter like the HKS one its more of a fuel type filter, it has been suggested the box of tricks in the glovebox was some sort of switchable map?