I'm not sure but from the pics I have seen a minirace is a maxflow racing BOV, or so Vortech now calls it. It's a nice, USA made cast unit with a machined top which is blue.
From what I understand there are two versions. One is called the "bypass" model and opens at around 5 inches of vacuum. It's adjustable from 10psi - 20psi for overpressure. This is primarily intended for draw-thru MAF type systems which Vortech uses. The excess boost is routed to the inlet of the S/C, so all metered air in the system (ahead of the MAF) is recycled.
There is also the "blow-off" valve which opens at 10 inches of vaccum for 20psi+ applications. YOU NEED TO HAVE A BLOW THRU MAF, and the valve needs to vent pressure PRE MAF. These make nice ricer trumpet noises that are great for 5 minutes until your girl starts complaining and your stuck in traffic.
Take this into account: my Vortech V1 S trim with straight cut gears whines and rings so much that any $300 BOV would have to compete with it's noise. Again, after we get our gutted mufflers and flow enhancers, we have a great muscle sound from our modular engines. Do we really need a chirpy whistle on top of that?
Here is low cost altertnative for a 12psi and under:
Bosch 101 BOV: $20 on ebay. It's fine for bypass and blow off.
Bosch 108 BOV: Looks similar externally but is the "Porsche" version. Has some bronze internals for longer life and tends to dump more than "flutter" Costs $80.
Oh, to answer your question, no BOV can increase boost. It's primary purpose is to vent (blow-off)or vent and recycle (bypass) boost pressure. If you don't got one in a high boost system this is what can happen:
Your crusin' along fat arming it and you gun the throttle only to have Johnny ricer with his civic cut you off. Your throttle snaps shut and all that compressed air in the system has no where to go. It then decided to go the only place it can= reverse back through your S/C. That creates a surging feeling, and wears your belt out FAST, maybe even a belt failure.
Ricer's invented the trumpet blow off valve that sound like a parrot caught in a meat grinder. It's all good if you have a 20+psi T Trim or D1 but for a V series it's just plain silly.