First i shoot a PSE longbow 60#@28,my draw lenthis 32" Fast flight string arrows are cedar 80-85# I currently use a 125gr 2-blade Magnus and I want to switch to a 160gr hill what should I do to Compensate for the drop.
Well, first, your shafts might end up too weak, assuming they are spined correctly with the 125s.
Once you get the correct spine sorted out, just go practice. If you're shooting instinctively, you'll automatically adjust to the new flight.
Why do you want to switch? The setup you have will shoot through anything in the lower 48.