Just thought this might be helpful to some of you guys out there.
So i don't get in trouble, lol this was taken off of ls1.com

A wet system has a fuel solenoid and a nitrous solenoid. So...the extra fuel that is needed when spraying nitrous is supplied through a solenoid and a jet. With a dry system you only supply nitrous to the engine but the nitrous is routed through the MAF sensor so that your engine's fuel injectors are instructed to supply the additional fuel. Your fuel pump must be up to the task in either case but your injectors must also be up to the task with a dry system.

The cons of a wet kit are that you have a fuel solenoid and if it fails, disaster strikes. There is only one N2O solenoid (if it sticks wide open, disaster), fuel is not distributed as efficiently or evenly, and fuel can puddle in the intake manifold (which was never meant to flow fuel saturated air) and cause an intake backfire, bottle pressure is crucial because it affects the fuel/air ratio, if the bottle goes empty during a run or the N2O flow is stopped for any reason your car goes extremely rich, and tuning is not done by the computer.

The ONLY reasons I can see to have a wet kit on an LS1 is that you want the capability to run an extra 25 hp shot on the stock fuel system or if you need to spray a really large shot (200 HP+) that would be too high for the MAF sensor to report. Still, even with that extra 25 hp I've yet to see an internally stock A4 with a wet kit and a stock fuel system run higher traps than what I've done with this dry kit. Trap speed equals power!

The cons of a dry kit are that if you want to go higher than a 125hp shot (or 150hp on a '98) you will need bigger injectors and soon thereafter, an additional fuel pump. With a wet kit you can go to a 150hp shot right off the bat and then you'll need an additional fuel pump if you want to go bigger but no injectors.



later,

allen