NOS Tech Info
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, the fuel injectors 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 single fogger wet kit are that you have a fuel 'noid and if it fails, disaster, only one N2O 'noid (if it sticks wide open, disaster), fuel is not distributed as efficiently or evenly, 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.

The cons of a dry kit are that if you want to go higher than a 65hp shot you will need an upgraded fuel pump. With a wet kit you can go to a 65hp shot right off the bat and then you'll need an additional fuel pump if you want to go bigger but no injectors.

The dry kits comes with a 10lb bottle with a nitrous pressure gauge, two small (Power Shot) solenoids with mounting bracket, 18 ft main line, two short lines, two nozzles, one "T" fitting, two jets, a FP cutoff switch, a micro switch, an arming switch, bottle brackets, a blow down tube, some fittings, and some electrical stuff. Ease of installation is opinionated but most folks get through it ok. It's just a bit aggravating with all the running of wires.

You should get some cooler plugs. I use NGK PFR6B-11 these are one step colder than the factory plugs on the Maxima, they are the stock plugs for the 300ZXTT (Thanks Don!!!) Generally, for every 50 hp that you add you need to decrease the gap by .004. If you add 75hp over stock you should decrease the gap .006. You have to account for all the power that you have added. Not just what you've added with N2O. So if you've added 25 NA hp and 75 N2O power you would decrease the gap by .008.

It is also recommended that you retard the ignition timing 2 degrees per 50hp. The only way to do this on the Maxima is by using the JWT NOS ECU Daughter board. Its ~$900 and only available for the 95 & 96 years of the 4th gens. This kit also controls the fuel flow for NOS runs. It’s the way to go if you have the $$$.

As long as you don't spray at too low of an rpm (below 2500 is getting dangerous) then you really have no need of a window switch on an automatic. You can manually engage the N2O at the appropriate rpm with your arming switch. On a 5 speed a window switch is a good idea. The window switch will allow you to launch at a low rpm and then the NOS will come on at where ever you set it (~3500rpm), this way you wont loose too much traction on launch. If your clutch lets go you will blow your motor. The window switch will turn off the NOS at where ever you set it (~6200rpm)

A fuel pressure safety switch (FPSS) is a must have device, but they sometimes come misadjusted from the factory. You can adjust it by turning the screw counterclockwise until it makes connection. I don't use one but I probably should. It has a spring in it that is defeated by the fuel pressure. So long as it is defeated, the circuit is connected but if the pressure drops, the spring extends and the connection is broken. When you adjust it you are just changing the preload on the spring.

Here are some other very nice but not necessary items...

A bottle heater (preferable the NX model since it is pressure actuated instead of temperature or manually actuated and much more powerful than the other brands to boot.)

A remote bottle opener is great for street use since you can turn the bottle on from the driver's seat. The NOS brand is a heavy-duty solenoid that attached to the bottle directly or is put inline away from the bottle. The NX opener is a literal bottler opener. It actually turns the bottle valve when you flip the switch.

A progressive controller allows you to set how much nitrous is sprayed out of the hole and how long it takes to reach %100. This is GREAT for adjusting for traction limitations!

With a cockpit mounted nitrous pressure gauge you'll never be in doubt.

You'll have no trouble with running 93 octane as long as you stay with ~65 shot or less. Even an 80 shot may work fine for you with 93 octane (it does for me) but I wouldn't try this unless you have an EGT gauge or A/F ratio gauge to see what is going on.


A purge kit makes for quite an intimidating show but if you want to save a little money you can get the same effect as a purge kit if you hit the spray briefly during your burnout. A second or so is all it takes. Having air in the line is really a bigger problem with a wet kit as it creates a rich conditions when the fuel flows and the N2O is not yet there. With a dry kit it just doesn't hit quite as hard with air in the line, which can be a very desirable thing if traction is a problem. You might just leave that air in the line if this is the case.

Ok, you've got your kit installed. Now what? Let's check to see if it will fire. With the bottle off, arm the system and have someone push the pedal to the floor. Does the WOT switch get tripped? Do you hear and feel the noid's click on and then off again when the pedal is released? If you have a FPSS you'll have to bypass it to get the 'noids to click with the engine off by connecting the wires to it together. Just screw them both to the same post of the switch. Ok, disarm it and open the bottle. Check for leaks.

I would suggest starting with the smallest jets you have for testing purposes and work your way up. A 65 hp shot is all you should spray with the stock fuel system

Approximate HP values for NOS single NOS Jets
HP NOS Jet
25 .024
30 .026
35 .028
40 .032
50 .034
65 .036
75 .040
80 .042

When you first make your test runs you need to check your spark plugs. If you see metallic specs (looks like pepper) on the white insulator part of the plugs you are too lean. Or if the ground strap on the spark plug looks like its anodized blue you are too lean. Adjust you system to compensate.

This is good info, if you have different opinions please post them, but no flames please.

*I edited this for our application from LS1.com, Forums, The Colonel's N2O Tech File!!! All credit to Steven Sanders AKA "The Colonel"

(info from www.maxima.org)

hope that helps some!!!