Vipers do not have fuel pressure regulators. The fuel system is built into the intake manifold and is returnless so pressure is achieved by the "dead" end inside the intake manifold. Just a pump fileter, fuel line, and injectors.
The regulator is built into the fuel pump sending unit which is in the tank. Like Smokin said, it is a dead head system and pressure cant be changed on the stock system. The factory rates pressure at 50 psi for idle and 55 psi for WOT on Gen 2's. Depending on what you are trying to do, there are ways to tweak the fuel system for more or less fuel volume and pressure. Unless you have a really good reason to do this, then I suggest you leave it alone.
I have a dry NOS system that I took off of my 2000 Mustang GT and was going to hook it up on my Viper, didn't want to spend $1,000 on a new kit if I didn't have to. Will this work? if so, how do I get the fuel to spike when I hit the bottle? Or do I need to buy the Viper NOS system?