After buying a used universal 4-6 cylinder ZEX dry nitrous kit i did a little further research when i ran into some tough spots during the install, and i found this out....

ZEX makes a kit specially for the 03-06 350z. It is a wet kit though. The difference is with a dry set up you are only spraying nitrous into the intake, with a wet set up you are spraying more fuel and nitrous mix into the intake. The reason this is safer (yes safer) is because of the way nitrous works.

Nitrous (N2O) is two parts nitrogen and one part oxygen per molecule of nitrous, as you may already know. When nitrous is injected into your car the heat causes the nitrogen atoms to separate from the oxygen atom, thus supplying more oxygen to your motor causing it to burn more fuel. This is where the power comes from.

With a dry set up you are burning more fuel, but where is the fuel coming from? Too much of this could cause your motor to run too lean which could very well lead to engine failure.....

With a wet set up you are supplying the extra fuel needed per amount of nitrous (distributed equally through jets matched for fuel amount and nitrous amount). This is done thru a tap installed (by you or a performance shop/mechanic) on your passenger side fuel rail - on Z's.

The kit comes with everything you need and detailed instructions with 3 sets of jets for 55, 75, and 100 HP. Depending upon which you have installed there is a chart that shows you which fuel jet to use matching to that nitrous jet (all jets included). Also is made for the Z specifically which means it is compatible with the throttle by wire set up on the Z - with complete instructions.

As far as 100 hp goes, this it what you need to do.-First, start off with 55 shot and use it for quite awhile until your engine/car/ecu is used to it.-After running 55 shot for awhile increase to 75 shot but you must retard the timing 2 degrees. Also run this for quite awhile until your car gets used to it.- Finally you are ready for the 100 shot (hp). Install the jets, and retard the timing 2 more degrees for a total of 4 degrees retarded from stock setting. -Note, anytime you upgrade to the next shot - you must use the fuel jet that is required for that shot, and be sure not to forget.-note this refers to the ZEX kit.

So it looks like i am selling the dry kit. The dry kit i purchased is a 55 shot and would be no problem on a mildly tuned car (like i have) but things aren't going to work so well with throttle by wire, and a kit not set up for that.... I am going to save up for the wet kit ($695).

This much power is worth my time and money. it would come out to $6.95 per HP at 100 hp - and $12.64 per HP at 55 hp...... worth it to me!

Hopefully i may have injected some knowledge in some, and helped some others.

-Ryan

very informative, I might add, taht while I have no experience with Zex or nitrous on a Z, my experience with other dry kits on other carsm they generally do make an effort to up the fuel, NOS used a jetted fitting going to the fuel pressure regulator, so when you hit the NO2 it pressureised the FPR raising the fuel rpessure,

also, when dealing with dry kits the ideal is to put the jet as far from the engine as pissible, ZEX makes great cone air filters with a jet made into the center which is perfrect for dry

Wet kits should be mounted as close to the engine as piossible as the further this volitle mixture has to travel the greater chance of it "falling" fromt he air puddeling in your intake and causing a potentially explosive situation, when running a wet kit multipoint is the only way to go

Yes the Zex kit does do the same with the fuel pressure regulator. Its just not as good and chances of uping the horse power / jets = tuning the fuel system. Also after talking with the ZEX guys about the ejector filter with nozzle, they said with a MAF sensor you want to spray after it so you don't gum it up causing failure of the sensor and/or improper signals such as false codes.

Good input though. If anyone else has anything, please post!

oh forgot MAF, MAF=FAIL, MAP + AIT FTW

Stock fuel pump should be fine then on a 03? Or would it be wise to get a walbro or new oem?