ZEX Nitrous Kit for
2005 Mustang GT
This isn't a full tutorial on the install but might be of some help.
The on the box claim is a 75 hp to 175 hp nitrous shot. The truth is, you should only setup the 75 hp shot on a stock engine. With a few more mods the Mustang should be able to take the full 175 shot.
As a Nitrous N00b, These are the most important points I found while learning about installing Nitrous Oxide in my Mustang GT taken right from the ZEX Manual.
"Spark plugs and nitrous performance: The factory spark plugs that come in the new
Mustang GT are not suitable for use with any nitrous setting above 75 hp. The factory spark
plugs are particularly hot heat range and tend to overheat at higher horsepower levels.
Attempting to use the factory spark plugs at higher horsepower levels can produce a
detonation condition after a few seconds of nitrous use. The solution to the problem is to
install spark plugs that have a colder heat range and proper ground strap design for nitrous
"Do not engage your nitrous system below 2500 RPMs. This ensures that you will
not have excessive cylinder pressures that could cause engine damage" The manual also says don't
hit your rev-limiter as this could be even worse for your engine than starting below 2500 RPMs.
"Make sure your vehicle has an adequate fuel supply. Nitrous systems put a
large demand on your vehicle's fuel system. Make sure you have a large enough fuel pump
to handle the demands of your engine, as well as the nitrous system."
"Engine computer modifications:...don't use any other non-nitrus tunes...yada-
yada... it is generally recommended that you retard the ignition timing around 2 degrees
for every 50 hp worth of nitrous used, based on an optimized ignition curve for your
"10. Check fuel quality & ignition timing. The last thing to do before enjoying your
new nitrous system is to ensure that premium fuel (92 R/M Octane or better) is in the fuel
tank and that your ignition timing is programmed correctly."
BASICALLY, if you want to go with any shot above a 75 hp shot you would need to do the following:
- Get colder plugs & have them custom gapped to .030 to .035. What does this mean and how much more does it cost than to buy the $100 spark plugs?
- Get more powerful fuel pump Is this easy to install because it seems they cost $700!
- Get a custom tune to retard my timing I have no idea how to do this but found that there seems to be a MSD Digital 6 box that has retard timing on it. That costs $320!
- Window Switch for safty's sake to keep my nitrous from engaging below 2500 and over 6000. Only $170
Total cost of reaching 100 shot: $1,290! + kit = $1,790
(note, this still doesn't include Purge Kit, auto bottle valve opener or tank heater)
So I got the Nitrous Kit in the mail. This is what it looked like: (click pics to see larger)
My brother-in-law and father-in-law helped out quite a bit. The first thing we noticed was the 2 hour install time was a load of bull. I could probably do it again in 2.5 to 3 hours now that Iíve done it once. First timers like me should set aside 2/3 of the day to goof-off, eat lunch and figure out where everything goes, then re-figoure out where everything goes.
Do like the manual says and lay everything out before you start the install. So I did. (click pics to see larger)
The air box was the only thing I had to take off
Once done laying everything out, time to get to work.
Start laying some hose down
Putting the bracket it was not as easy as I thought it would be. Once you pull the carpet up, you'll find everything is an un-even surface and drilling in what you think is a good place might end up being trying to drill through a vertical sheet too. (I have a 5th, un-wanted hole in my trunk.) After finding what I think was the most suitable location, turns out I had to bend the bracket to fit the contour of the trunk bed. After everything was all said and done, that torqued bracket worked out great. Turning on/off the bottle is a little tight, but easily doable and I saved the maximum amount of trunk space.
Under the hood: Be sure to tighten then re-tighten ALL BOLTS under the hood. I had fuel leaking from at least 2 nuts. Luckily, we caught that in the post-build-pre-flight check.
The Nitrous installation was a success. I tried the 75 shot the following day...
I just wanted to see how fast I could get up to speed on the freeway. So I picked one of
my favorites on ramps. It features about 100' elevation with a nice even level-off so it
feels like you're in a jet taking off.
- Armed the NOS,
- I made the right-hand turn onto the freeway on ramp.
- Wound the engine in 1st to 2500 RPMS
- Slammed the gas (heard a click under the hood),
- a split second later i was at 6,000 and snapped it into 2nd
- Wound it clear to the end of 2nd gear and jammed it into 3rd
- 100 MPH! COMPLETELY BY ACCIDENT! I found my foot STUCK to the accelerator! I
mean PLANTED! Using all the self-control I could muster I pried my foot off just in
time to slam the breaks back down to a more reasonable, less ticket-prone 70 mph.
My heart was pounding, adrenaline was pumping and then, I remembered, humans need
to breath to live. And with that thought I left out a huge
What a rush! Worth every penny! All I could think about was, my next shot. I had to
have another. And for those of you who have NOS, you know what I'm talking about.
Some say I need help, well I could stop any time I want.
The actual path taken on first use of Zex Kit.
I finished installing the arming toggle switch so I don't have to use the dumb looking cigarette-lighter plug in switch.