Then, you *should* be able to get *something* (if not much) out of this.
The idea behind it is, more air in = more explosion = more power.
However, you can only "pull" air in as fast as you "push" it out. The activity of the engine is what's the creating the vacuum. Generally speaking, the 22re is fairly balanced on this already in stock form. So, if you were to JUST open the intake, it will not really suck in much more air b/c it is still limited by how fast it can get out on the other end. However, by opening the back end more, it changes the equation, and you can now get more IN. Changing cam profile helps this too.
As Oops has pointed out, you will only benefit when the amount of air coming IN is about the same as going OUT. Colder air is more dense, more air per unit volume, so it works better for this than warmer air.