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.
There are quite a number of boost controllers available in the market. Perhaps I would list down a few such as HKS EVC, BLITZ Dual SBC Electronic Boost Controller, Apexi AVCR Boost Controller, SARD...