70 dart swinger slant turbo build and mild restoration

Oh no, it's possible. But I wouldn't set your goals by pressure. Instead, go for power or timeslips. If you build it right/efficient you won't need even 20psi. The fastest slant in the world only runs on 15psi (i believe). The most powerful slant in the world makes north of 600 horse with 17psi. But people have also thrown 28 pounds of boost to a slant and just barely breached 300hp. Read read and read before you buy anything though. Learn how to read turbo maps and size turbos. Either pay to have your head ported or learn to port on your own (slant heads are easy). Learn to size cams for turbo apps. I feel all of these are vital.