The VJ14 won't do 18psi. Neither will an 11/14
16psi is the max
reliable amount of boost they can push, any more is overspooling resulting in superheated air and drastically reduced turbo life.
Your bottom end could probably take the 18psi for a while, but you'll need to find a different turbo first. I also can't recommend my chip for anything past 16psi, either