How to: Install NX Wet kit, Duel zex purge, and nx window switch

Jhun35 · 07-16-2012, 08:07 PM

*Warning, This is a Long How To* - I will have to take more pics as I get around to it. sorry if some parts don't have pics yet.

Okay guys. I have been wanting to put this how to together now for a couple days. I’m going to show you guys how to install a full nitrous kit, with purge, window switch, the whole ordeal. Only thing you won’t see how to install is a bottle warmer, fuel pressure regulator or remote bottle opener, but once I get those I will add them in.

Okay first off, the kit I have is the NX (Nitrous Express) Stage 1 EFI kit, Duel Zex purge kits, NX non digital Window RPM switch, with ZEX bottle brackets and a NOS 10lb bottle. My kit was pieced together using some used and some new parts, but most kits will include everything you need. The purge, window switch and tach adaptor are separate though.

What you will need:

*Nitrous Kit*
Nitrous Bottle of your choice, (I recommend it has a high flow valve)
Bottle Brackets
Nitrous and Fuel Solenoids
WOT Switch and Toggle Switch
NX Relay w/ wire harness
Shark Nozzle with Adaptor fitting
Bag of Jets
Feed Line (10-15ft, suggest 15ft)
Nitrous and Fuel lines
Homemade Fuel T
Metal Brackets for mounting solenoids/WOT switch

*Purge Kit*
Purge Solenoid(s)
Purge Nitrous T(s)
Purge braided line(s)
Compression Fitting(s)
Metal tubes or hose for release
Brackets for mounting solenoids
Purge button

*Window Switch*
A Window switch of your choosing (I used NX)
Brianj Tach Adaptor (Pm him)

Window Switch

Tach Adapter

*Other items you WILL want to pick up*
Extra wire, multiple gauge
Butt connectors
Wire Loom
100-200psi fuel line
Hose clamps
Add a fuse(s)
Thread sealer or thread tape
7.5amp and/or 10amp fuses
Male/Female lead connectors
Silicone Gasket
Zip Ties

Process of installation:

1. Okay, now this is going to take a lot of planning. The first step is going to be this. I want you to sit down, or look at the car, and kind of map out how you are going to run everything. How to run your wiring, where to mount your solenoids, where to mount your bottle, switches, etc. Try to know exactly what you want to do before you start. You can use my methods as an example, or a blueprint. Once that is done, let’s start mounting the solenoids.
How mine are mounted:

2. Okay, what I did was mount my solenoids, and then determined how much wire I would need in between to start merging them. The cool things about these solenoids are they are an open current. Meaning either of the two wires coming from them can be used as the ground or hot wire. So first, take one wire from each solenoid, and run them together, measure how much you need and cut them. These are going to be your ground wires. Go ahead and solder or splice them all together, and find where you are going to ground them. I grounded mine on the bolt holding the electrical bracket to my tb. As seen in the picture below.

Here is where I grounded my second purge solenoid

3. Now take the other wire from your nitrous and fuel solenoid, connect them, then take the other wire(s) on your purge solenoid(s) and connect them. DO NOT MERGE YOUR PURGE SOLENOID(s) HOT WIRE(s) WITH YOUR NITROUS AND/OR FUEL SOLENOIDS HOT WIRES, THESE RUN TO DIFFERENT PLACES.

4. Okay, while we are mounting things, find a spot in your engine bay to mount your window switch. This needs to be in the engine bay to prevent a wiring headache. I mounted mine to the side of my ecu cover. Make sure to put your rpm modules into the switch.

5. Let’s jump to the next most annoying part. Mounting the bottle/brackets. You can take my idea, or develop your own. I didn’t want to drill through my trunk cover, or any more holes then I needed to, so I decided to innovate. I pulled the piece of carpet that covers the rear cross member that runs under my rf sub. It is held down by two plastic clips. Make note of where these clips are located. I then took a piece of steel, cut it down to 16in X 8in sanded it down and painted it black. I then found four bolts, two shorter than the other. So I could use them to mount my brackets. I put my bottle in the brackets, and lined it up to exactly where I wanted it to be, and marked the bolt holes. I then spot welded the four bolts to the piece of steel. I repainted it one more time, and secured my brackets using locking nuts. I went back to the car, and decided to use the two holes where the plastic clips were located, to secure the new piece of steel to the car. I used grease to mark the two holes, drilled them, and used two big self tapping bolts to secure it down. And there you have it. Bottle mount/brackets.

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6. Next let’s set up our purge line(s). You should have a purple purge T if you have the same zex kit. You need to secure your fitting onto the T. Like so:

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The Purge T(s) connect to the “In” port on the nitrous solenoid. Your feed line runs into the T. So should go like this: Bottle>Feedline>purge T>Nitrous solenoid>shark nozzle>intake
Now run take your -3a purple capped braided line(s) and run them(it) from your T to your “in” fitting(s) on the purge solenoid(s), as seen below.

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7. With that out of the way, you can now go ahead and run your feed line from the nitrous bottle to your purple purge T. If you don’t have a purge kit, just run directly to the “In” port on your solenoid. We have two options to do this.

The first option:

A. Running it underneath the car. To do this, you will need to drill a hole in your trunk. Go ahead and attach one side of the line to the bottle. Find out where you want to drill and run it. Scope it out from under the car, so you don’t accidently drill into your fuel tank lol. You’ll want to use some type of rubber grommet to keep the hose from smacking against the metal edges of the hole. Drill your hole, and feed the line through. Make sure you have no stress on the line anywhere. Follow your fuel line, which should be down the drivers side, zip tie so often. Run it up into the engine bay, still following the fuel line, then over to your nitrous solenoid. Make sure to zip tie in multiple spots to keep it from bouncing around.

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The second option:

B. Another common option on other forums is to actually run it inside the car, and out through the firewall. In this case, it would be easiest to run down the drivers side, behind the side panels, and out the rubber grommet in the drivers side fender (where we will be running wires). To do this you will have to cut or drill a hole in the grommet, then push the hose through, run it up behind your headlight (see pics below), and over to the nitrous solenoid.

8. Find a way to mount your purge/nitrous toggle switch(es). This is another thing involving preference. I decided to use my blank button (traction control switch location) and spot for my fog light switch to house the nitrous buttons. To give it a nice oem flow. This is what mine look like:

After you have figured out where to mount your switch, we get to do the best part, WIRING.

9. I chose to wire everything I could up first, to make sure all the solenoids worked correctly before tapping into my fuel line and intake. This is the worst and most tedious part. Here are three diagrams I used to help me wire everything.

http://www.nitrousexpress.com/Instructions/stage1.pdf
http://www.nitrousexpress.com/Instru...ndowswitch.pdf
http://news.compperformance.com/Instructions/ZEX174.pdf

*For all wires running from inside the car to the engine bay, I suggest using the driver’s side fender grommet* See below:

Okay, I’m going to try and make this wiring schematic as universal as possible. I merged a ton of wires so I’m going to break it down to every wire running individually so people who don’t have the same items I do can wire it still. First, start with purge:

A. Purge is the easiest, hence why we are wiring it first. This is literally two wires. Take the hot wire(s) from your purge solenoids, and run them inside the cabin. Use a female lead and connect the wires lead to one of the leads on the purge switch. It doesn’t matter which one. Now connect a wire lead to the other switch lead. You need to connect this second wire to a 12v switchable line/fuse. I used fuse slot number ( ) to do this. For now, just wrap it around the prong on the fuse, and shove it back into place *Don’t use your add a fuse just yet*. Turn the key on, but don’t start the car. Push the purge button a couple times, you should hear a click each time, if you do, congrats the purge setup is wired correctly, if not, double check your wiring for loose connections. Go ahead and pull the fuse back out and disconnect the wire for now.

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B. Window Switch/Tach Adaptor will be the next journey. This is pretty simple. If you have the NX switch, then there are four open ended wires; red/white/black/yellow, and two looped wires; red and blue. If you have a GT, then you need to cut the red looped wire, if you have a GS you need to cut both the red and blue looped wires. Not sure why, but it’s in the instructions. Next, run your black wire to a solid ground in the engine bay. Run your red and yellow wires into the cab through your firewall/grommet. The red needs to wire into a 12v switchable source (see why I said not to use your ‘add a fuse’ yet??). The yellow wire needs to be soldered/spliced together with the white wire from your nx nitrous relay harness, (The yellow wire acts as a circuit ground wire, it connects to the ground side of the device you plan to activate.) Now let’s look at your tach adapter. The brianj adaptor should have one green wire and 4 brown wires. The white wire from your window switch needs to be connected to the green wire on the tach adaptor. The four brown wires need to be connected to pin #3 on each coil pack plug. Start with cylinder 1 and work your way up to 4. The colors of the wires you’re tapping into are as follows: Black/blue, white/blue, gray, and pink/black. You may not need to connect to each cylinder. Start by just doing cylinder #1, and we will come back to this after testing.

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C. Now the fun part. Wiring the nitrous buttons, solenoids and tying it all together. Let’s start right at the toggle switch. You need to connect a wire to the top lead (labeled ground) and connect that wire to a solid ground. Now connect a wire to the bottom lead on the toggle switch, this wire runs to a switchable 12v source (once again, can use the same fuse). Go ahead and connect a wire to the middle lead on the toggle switch. This will run from the toggle switch to the rear lead on the WOT switch (this is the lead that comes out at a 90degree angle from the switch). Connect the red wire from your relay, to the other lead on your WOT switch (one that sticks straight out). Run the black and green wires from your relay out the firewall and into the engine bay. You need to connect the black wire from the relay to the positive terminal on the battery, like so:

The green wire needs to be connected to the hot wires from your nitrous and fuel solenoids. Now hopefully you have already connected your white wire from your relay to the yellow wire from window switch (IF YOU DO NOT HAVE A WINDOW SWITCH, THEN JUST CONNECT THIS WHITE WIRE TO A GROUND!!), if not do so now.

*Here are a few pics of wiring and the headache*

*Testing Wiring* - Okay so we have now already tested the purge, lets test the nitrous solenoids, and then the window switch. First, once again turn the key on, but don’t start the car. You will want to have someone there as an extra set of ears. DO NOT HAVE BOTTLE OPEN DURING TEST!!! Go ahead and push the hot wire from your toggle switch into the fuse, but not the red wire from the window switch. Flip the toggle switch up, and the press on the WOT switch a couple times, you should hear the solenoids click. Have someone listen to make sure both are clicking. Now flip the toggle switch off, press the WOT switch to make sure they solenoids don’t click when it’s off. Flip on, push, flip off, push. Do this a couple times to make sure. Now, pull the fuse out, and wrap the toggle hot wire AND the window switch hot wire, and push the fuse back in. Now, start the car (yes, start all the way), still no bottle hooked up. Flip your toggle switch up, and push the switch if you hear a click, then you need to wire in another brown wire from the tach adaptor. Remember how I said to start with just one cylinder? If you hear a click, wire into coil #2, then #3, then even #4 if you have to. But you shouldn’t have to use more than one or two. (If you use all four and it still clicks, you need to double check your wiring.) If you don’t hear a click, then here is the next step. Sit in the car while holding the WOT switch, rev your engine up to the rpm where your window switch should activate (in my case it’s 3k rpms), rev a little past that mark, and push the WOT switch, you should hear a click. If not, once again something is wired incorrectly. This is meaning that the window switch is only allowing nitrous to engage at or past 3k rpms, and disengage at another set rpm module (mine being 6k.) If everything has went smooth so far, you should be good, but, if you want to make 100% sure, rev up to 6100rpms, and press the switch, if it clicks, that isn’t good, because it should’ve been disengaged by now. If it doesn’t click, your window switch is working properly. Hopefully all went well. Go ahead and use your “add a fuse” to connect all the 12v switchable wires to a fuse, clean up the wiring a bit inside.

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10. Phew, glad the wiring is done, (hopefully anyways). Since we are already in the cab, lets go ahead and mount the WOT switch. There is a bolt right behind the gas pedal that works perfectly. In order to make it work, you need to bend you bracket at a 90 degree angle, and cut off the top hole, like this:

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You also need to bend about an inch of the actual toggle switch, back at a 90 degree angle to make it fit. Go ahead and position the toggle switch so that it engages as you are going into WOT, then tighten down the bolt to secure it in place!

11. Now for the very final steps, but the most testing, mind boggling steps of them all. As quoted by the great Broly on c4g, “Not for the faint of heart”. Let’s start with tapping your fuel line. Hopefully you have already made a homemade t similar to this:

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You can get everything you need in the plumbing department at Lowes. You need to start by depressurizing your fuel lines. Easiest way to do this, is to pull the fuse for your fuel pump (can’t remember exactly which one, check the service manual), and start the car. Let it stall out. Or you can lift your back seat, and manually unplug the fuel pump instead of pulling the fuse. In order to get to the fuel line, you will have to remove your intake, and possibly even your battery, so go ahead and do both of those. Now remove your hard piece of fuel line that connects to the fuel rail. It’s held on with a red tab. Now remove the other end of it, from the metal piece of the fuel line that is behind the battery. Right here:

This can be tricky. The plastic piece actually flips up, and then you can pull the line up and off. It may take some examining to figure out how to unclamp it. Now take the fuel hose you bought and measure it out to go in place of your original. I’d leave enough room for two fuel T’s incase you decide to get a fuel pressure gauge (which you should with nitrous).

Cut the hose where you plan on placing the T. Take your home made t, and slide the hoses over each side, and clamp it down with the hose clamps you bought.

Place the hose in place of the fuel line, and clamp it down with the clamps. Tighten everything up VERY tight! You will leak gas otherwise. I actually ended up double clamping the hose because mine kept leaking. Get it as tight as you can. Now run the -4a red tipped braided line from your fuel t to your “In” on the fuel solenoid. Tighten the braided hose down using two wrenches. Get it as tight as possible to keep from leaking gas.

12. Next is the most fun part, tapping into your intake. Take a drill and drill a 9/16th’s hole into your CAI. Notice where my shark nozzle is:

It needs to be between the tb and MAF. Make sure to clean the intake out of any metal shavings. Take your shark nozzle fitting (the bolt side, not flat nut) and apply a bit of gasket. Insert the fitting from inside the CAI tube. Hold it there and screw the nut onto the fitting. Apply a bit more gasket onto the outside of the intake, and tighten down the fitting/nut as well as you can. Now go ahead and screw in your shark nozzle. Get it as tight as possible and make sure it’s pointing towards the TB.

Put your car back together and reinstall the intake. Now take the -3a braided lines from the “out” fitting on your nitrous and fuel solenoids to your shark nozzle. Make sure you put the jets that you want in too. Tighten these down nice and tight with a wrench.

13. Last but not least, let’s run your purge line(s)!!! Use your metal tube(s) or hose, and attach them to your purge solenoid(s) using your compression fitting(s). Run your hose(s) where you want and zip tie them into place.

And there you have it!! Just make sure to tighten down all your hoses by double wrenching, clean and tuck your wiring with some wire loom, and start the car and check for any gas leaks. After that you should be good to go!! If anyone has any questions please give me a shout. I’ll be more than happy to help however I can.

**mrg7243** · 07-16-2012, 09:39 PM

Who wants to take bets with me? Being serious paypaled $5. The bet it how long it takes to blow his motor and for a how to rebuild your motor followup.

I am sure you put alot of work into this but what about tuning??

**finald8ta** · 07-16-2012, 09:48 PM

Originally Posted by mrg7243

Who wants to take bets with me? Being serious paypaled $5. The bet it how long it takes to blow his motor and for a how to rebuild your motor followup.

I am sure you put alot of work into this but what about tuning??

im down.

Jhun35 · 07-17-2012, 12:48 PM

Originally Posted by mrg7243

Who wants to take bets with me? Being serious paypaled $5. The bet it how long it takes to blow his motor and for a how to rebuild your motor followup.

I am sure you put alot of work into this but what about tuning??

I have the reflash by hackish with a nitrous tune retarding timing 2-3 degrees from 3000rpms and up. Raised rev limiter to 7200rpms. This tune also adds fuel at WOT after 3000rpms. The window switch is what protects you from blowing up the engine. It prevents you from injecting too early, causing the nitrous to pool up in your manifold, or injecting to late, causing you to hit fuel cut, leaning out, and frying a piston.

The 4g69 has forged internals, with the exception of pistons. It was initially built for turbo, considering it's in the old lancers. A little nitrous 101. Nitrous works exactly like a turbo. It injects nitrous, which is colder than regular oxygen, thus allowing denser air into the engine, raising compression and making more power.

Another thing, please take a look at the eclipse forums. There are plenty of members who have been running 120hp+ shots of nitrous on the 4g GS on stock internals, with no tune, and have been for years without any issues. That's dumb, but shows how well these engines are built. I'll take the 4g69 over the 6g75 any day because it has so much more potential internally. Plus the ability to swap parts from the 4g63 and 4g64 internals, along with their aftermarket support, makes this engine perfect for boosting or forced induction.

Jhun35 · 07-17-2012, 12:52 PM

Another smart move is to have the following. Like me:

Window switch
AEM UEGO wideband
Fuel Pressure gauge
fuel pressure regulator cutoff switch

These will prevent you from blowing your engine. Allows you to determine when to inject nitrous, when to stop. Lets you see when you take a fuel cut, when you're about to lean out and will actually stop injecting nitrous if your fuel pressure goes below a certain psi.

It's extremely easy not to blow up yiour engine. would I do this on a engine that wasn't built for it? Hell no. But the 4g69 engine? Hell yeah. I'm tuned and have all the necessary accessories to make it work correctly and safely. Plus there have been too many people use nitrous on club4g and c4gnation and never had an issue. Only one guy has messed anything up on their engine. His was the v6 GT 6g75 engine, spraying a 150 shot. He didn't even mess up the engine, just fried his pcm. But there is no way to determine if that was nitrous related or not. I'm only doing a 75 shot, and I'm reflashed / tuned for nitrous.