I would hope not. 20psi on pump gas will be borderline idiotic I think. I've heard of guys running that much, but I would be afraid of detonation. You'll probably get somewhere around 15psi if I had to guess, but I could be way off. The boost cut is there for a reason, so don't try and fight it. Do the correct mods to your car and you can run a little higher boost. Good luck.