Horsepower change?

I talked to Wilson manifolds today about the 3x intake. They think it could help to rework the plenum. I asked about POTENTIAL HP gains knowing that there is no way to know results with mechanical injection. He said MAYBE 20 TO 25 HP GAINS due to fixing the plenum area.
The DLC coated pins ought to help. Vacuum won't hurt them.
I assume i may see 20 hp just from higher vacuum.