The seperator plate won't change shift firmness but drilling the holes will. Not huge difference. The real difference in shift firmness comes from removing accumulator springs. Even with all of this done you can still back off the shift pressures in the tune or with the SCT hand held. Mine shifts are crisp and fast. On a 3/8 throttle romp from a stop light it will chirp the rear tires on the 1-2 shift. Love it like that.