FX Another Impact tune question

So I’ve searched and searched previous threads for a tune for my impact and haven’t found what I’m looking for. I have a .22 cal impact, 600mm with a heavy slug liner. Everything else is stock. I plan on shooting 31.2 NSA slugs. All the tunes I’m finding are for rifles that have power slug kits and other upgrades that I don’t have. Do I really need to have the power slug kit to maximize performance? If not, what would be a good starting point? Thanks in advance.
 
I doubt you need the slug power kit. I have the same gun and liner and shoot 27.5 gr NSA’s @ 975 fps. The gun is not working to do that. 2nd reg is 142’ish and my micro wheel is about 3.5. The valve knob is just a shade under the 4 line.
With your slug weight I would start at 145 bar, big wheel somewhere near the middle setting and the small roller on 2.5 and work it up from there. You may have to use a higher 2nd reg setting but believe it can be done without adding anymore fooforah to the gun.