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.
i'm using this thread to gather parts number for our car. seems like there are many stuff that i need to replace for my car and after asking the price and some shops, i'm a bit scared. so i decided to try...