I would personally blend and get rid of any casting faults on the shorturn. Then set you pinch to .950 then flow it again. I automatically do my pinch to the tube and then I push my common wall over to my head bolt tube but this exercise is to see what someone could gain easily and on a budget to possibly see 500 plus horsepower. Most guys aren’t going to go over a .570 lift cam so those numbers you gained from .250 up are golden. You can check airspeed right??? After those mods I would check your speed at the pinch and short turn.