I will try to answer your question a little more in depth.
There are a few different NOS setups.
1. Dry manifold System
2. Wet Manifold System
3. Direct Port System
4. JWT Dry Manifold System
1. Dry Manifold System - Consists of 2 Nitrous solinoids and a NOS fuel pressure regulator. This systems is activated with a microswitch on the throttle body at WOT at any given RPM in any gear. Once the nitrous is activated , nitrous passes through the 1st NOS Solinoid , then passes though the NOS Pressure regulator. This bumps up your fuel pressure via your stock fuel pressure regulator. Passes through the second NOS solinoid and comes out through a nozzle placed as close to the throttle plate as possible.
2. Wet Manifold System - Consists of 1 Nitrous solinoid and a Fuel Solinoid. This systems is activated with a microswitch on the throttle body at WOT at any given RPM in any gear. Once the nitrous is activated , nitrous passes through the NOS Solinoid and routed to the "Fogger"nozzle, at this same time fuel passes through the Fuel Solinoid, which is tapped into your fuel line, and is routed into a "Fogger" nozzle. This "Fogger" Nozzle atomizes the fuel and nitrous before it enters the intake planum. This nozzle should be placed at least 12 inches away from the throttle plate to insure atomization.
3. Direct Port System - This system works exactly like a wet manifold system except rather than having one "Fogger" nozzle , you have one per cylinder plumbed into the intake manifold, hence the name "Direct Port" . This is a very aggressive , nitrous kit installed on most of the 11 second all Nitrous powered cars. This is usually controlled with a NOS Nitrous Master which can adjust % of nitrous entering the system per RPM.
4. JWT Dry Setup - This system is essentially a NOS Dry kit minus the NOS fuel regulator. JWT tunes the ecu and uses a NOS Module to switch the fuel and ignition maps when the nitrous is activated. There are 2 setups , a 50 shot which uses your stock injectors or a 100 shot setup which uses 370cc injectors from a Q45/300ZX TT. The 50 shot is activated at WOT @ 2000 rpms. The 100 shot is activated at WOT @ 4000 rpms. This system is used with one Nitrous solinoid from JWT. Ben B and myself both used 2 Nitrous Solinoids inline just as an added safety feature just in case one solinoid ever stuck open the second one would then close. You should launch with slicks out of the hole while the NOS is activated. All you have to do is activate the switch, Rev your motor at 5500-6500, drop the clutch and let the NOS do the rest of the work.
I hope this helps!
Louis Anaya 1992 Sentra SE-R
349.6 hp & 288.9 ft/lb @ 19 psi, 13.6 @ 111 mph(Street Tires),12.7 @ 112 mph(Slicks), Bluebird SR20DET w/ GTiR Pistons,T3/T04E,Deltagate Wastegate (7-9 PSI) FMAX Manifold, RevHard FMIC, JWT S3 Cams, JWT Ported & Polished Head, 1996 200SX SE-R Welded & Cyro Treated Tranny, ACT Xtreme P/PL & 6 Puck Disc, Cobra MAF, JWT ECU w/ 4 Bar Fuel Program, MSD 50lb/hr Injectors, JWT Fuel Rail, 300ZXTT Fuel Pump, AeroMotive Adjustable Fuel Pressure Regulator, Greddy Type "R" BOV, Greddy Profec B, Greddy Boost & EGT Guages, UR 4 Pulley Kit, Powerslot Rotors, Axxis MM Brake Pads, ES Motor Mounts, Topspeed Short Shifter, Momo Cobra Shift Knob, KYB AGX Struts, GC Coilovers (350F/600R)& 17x7 White Tenzo Shu-4's w/ Sumitomo 205/40/ZR17 Tires (Street), 13x7.5 White Lenso VPD's w/ Mickey Thompson 24x8x13 Slicks(Drag)