If you increase the valve pressure (turn in the screw), you increase the valve's resistance to opening at lower vacuum levels, meaning part throttle or at idle but you also increase the occurrence of compressor surge, which is what a BOV is there to prevent in the first place.
Guys,Among 5 screw rod, mine patah 1 already. Tried to change my puncture tyres last night..until the one of the screw patah!. Luckily got 4 more wheel screw rod,hopefully car safe to drive la.Pls advice me who have...