Bustin' Loose With A Little Juice

I have a confession to make. After years of being in denial and carrying around the fear that goes along with nitrous oxide usage, I have to admit that I have officially graduated to nitrous junkie status! As mentioned in our past two Focus stories, we had (and still do have) plans to install a turbo kit from Precision Turbo, but as the testing on that piece continues, we elected to make up some lost time with a little bit of laughing gas.

Since this would be my first experience with the jug as far as my personal car goes, I was a little nervous and had a ton to learn about the proper dos and don'ts when using the force-fed additive. With a best time prior to the nitrous install of 16.907 at 79.99 mph, we were happy and surprised our factory automatic Focus ZX5 could run that quick, but like all gearheads we wanted much more--enter nitrous oxide.

After trying for months to weasel my way out of it, the big guy across the hall, Editor Jim Campisano, laid down the law and scheduled a nitrous install on The Red Hot Chili Pepper. No doubt our 16.90 e.t. would be lowered dramatically with the spray, but I knew nothing about nitrous usage. Regardless, I took off my skirt and panties and began researching different nitrous kits for the Focus. One company that offers a dynamite setup is Nitrous Express in Wichita Falls, Texas. They had been around the game for decades and know the beast inside and out.

NX Marketing Manager Randell Mathis and I struck up a conversation and he recommended we install its NX Stage 1 kit onto our Infra-Red five-door. The Stage 1 kit works with the factory fuel system and computer and does not require a timing retard feature to be used. This cut down the cost and sophistication factor for sure, as well as simplifying the installation process.

Before we begin, let's first explain how nitrous oxide works, how it generates additional power and why some racers (myself included) are a little intimidated by it. "There is no reason to fear nitrous use," explained Mathis. "The main reason why people are afraid of the stuff is because they don't use it properly, engine damage results, and the nitrous is the easiest item to blame. The truth is if used correctly, nitrous oxide is just as safe as a supercharger or turbo kit.

"Nitrous consists of one part oxygen and two parts nitrogen. When injected into the engine, nitrous turns into pure oxygen when it reaches 563-degrees Fahrenheit. The nitrous gets heated when it becomes injected into the cylinders of the engine by heat from the combustion chambers and, when mixed with extra fuel, will generate loads of extra power."

We then asked Mathis why a wet system (nitrous and fuel) is preferred over a dry system (nitrous only) and he said that a wet system doesn't require the computer to be re-calibrated because it [the nitrous] gets injected after the mass airflow sensor.

"By using a dry system, you will have to locate the nozzle before the mass air sensor and after the sensor picks up on the additional oxygen (nitrous) it will have to re-calibrate the entire system in order to compensate the nitrous with extra fuel," he said. "It's much easier to just add the extra fuel right at the nozzle with a fuel solenoid. Also, in back-to-back testing, we have found that a wet system will generate much more torque when compared to a dry kit. Our kits can add over 50 lb-ft of torque more than a similar dry system. Injecting the nitrous and fuel right at the nozzle is the main reason why a wet system works so well."

Installing The Stage 1 Kit
We began by removing our Steeda cold air tube so we could drill the appropriate hole in it to mount the nitrous nozzle, known by NX as the Shark nozzle. It attaches to the tube with a threaded fitting that protrudes through the 9/16-inch hole in the tube you just drilled. The NX instructions indicate that, for optimum performance and atomization, it should be mounted between 2 and 6 inches from the throttle body.

"Our Shark nozzle has what we refer to as a Bath Tub tip on it," said Mathis. "The tip injects the fuel in front of the nitrous for a much better atomization between the two. The design on the tip of the Shark nozzle creates a swirling, vortex-type pattern of nitrous and fuel, equaling more power." With the nozzle in place, we re-installed the aluminum inlet tube and began searching for a good location in which to mount the two solenoids. You wanted to keep them away from heat and moisture and the best location we came up with was on the driver's side of the engine, on a bracket that is connected to the cylinder head (used for removing the engine). With the solenoids attached to the steel bracket, we grounded one wire from each solenoid and attached the braided lines from them (with jets) to the Shark nozzle.

Next we attached the relay to the driver's side strut tower and connected the four wires to the proper locations as per the NX instruction sheet. "The green wire gets routed to the solenoids (to activate them), the white wire goes to ground, the black wire is your constant (battery) power source and the red wire is for your activation switch," explained Mathis. "It is really simple and should be done exactly as the instruction diagram shows."

The next step was to bolt the bottle brackets in the hatch area and mount the 10-pound nitrous bottle. After drilling four holes in the floor, we tightened the bolts and placed the bottle inside them.

"It is important to angle the braided nitrous line fitting in the downward position in order for the siphon tube [in the bottle] to operate at its best," Mathis recommended. "Otherwise, you might not have the proper amount of nitrous flow [to the tube in the bottle] and the true potential of the kit will not be experienced.

"As far as filling the bottle goes, a good rule of thumb is that for every 10-seconds of nitrous use (with a 50-horse jet) you will use approximately .4-pounds of nitrous. Usually, you can get between 10 and 12 runs before needing to fill the bottle at this level. At optimum temperature (1,000 psi) it should last for quite a bit of runs."

From there, we had to route the 4-AN nitrous line from the bottle to the nitrous solenoid, located under the hood. To our good fortune, there was a rubber grommet under the rear seat, located on the floor that was just perfect for our line routing. We made a minute slit in the rubber, fed the nitrous line through it and routed it up the side of the frame where it was connected to the bottom of the nitrous solenoid.

"It is wise to flush out the nitrous line prior to connecting it to the solenoid," explained Mathis. "You can do this with compressed air and it is extremely important to rid the line of any debris it might have in it. The inlet port of the solenoid does have a filter (screen) in it, but it can become clogged with debris and hurt flow."

Did It Work? Did It Eever!
At Old Bridge Township Raceway Park, I first made a non-nitrous pass to establish a baseline and on this day she topped out at 17.001 seconds at 79.59 mph. We then backed up that run with a 17.05 at the same speed. The 60-foot times were nothing to brag about either. Our best was a yawn-inducing 2.43. With the kit armed and ready, we hit the ignition key, checked to verify the solenoids were operational (they must both click when the button is depressed) and made a path toward the starting pad. With the bottle cracked open and my right thumb hovering over the arming button, I power-braked the engine at 2,500 rpm and let it rip when the light turned green. On the first run, I still had some trepidation and was way too conservative with the button. Still, on the first nitrous pass, I bettered our 17.00 at 79.59 mph with a staggering 15.469 at 90.76 mph (2.40 60-foot). While this was impressive, I was way too cautious with the button and knew that something better--a lot better--was in the cards. After a lengthy cool down I made my way to the line for the second attempt.

Squirting the car out of the hole dropped our 60-foot time to 2.22 and at the stripe the scoreboard displayed a mind-bending (for this car) 14.925 at 89.66 mph--and this was only with the 75-shot jetting. That's a solid 2.076-second improvement and is not a bad way to spend a mere $629. Imagine what we could have done with a 100-shot. Mathis explained to us that the factory fuel pump would never keep up with more than a 75-horse jet and he doesn't recommend using more than the 75 pill, but you can run 100-horse jets with the proper fuel system in place.

One thing we did notice was with the jug on, the transaxle dropped from 7,000 rpm to 3,000 between shift points and took, I don't know, about five minutes to decide what gear it wanted to go into. For Focus owners who plan on using nitrous or a turbo, a quality transaxle overhaul (and aftermarket converter) should be in the cards. The OE trans is simply not designed to handle the extra load of a power adder and will wind up failing over time. We are now in love with our newfound power and, after installing our turbo kit, we might even kick down the jetting in the nitrous and try using both of them together. Think about it for a minute, a heat-generating turbocharger with a small shot of nitrous on top of it. Can someone say warranty claim?

We fed it through and directed it along the chassis and up to the engine with Zip Ties.	With the nitrous line and bottle completed, we shifted our attention to the wiring. The NX kit comes complete with its own relay, which we attached to a metal tab on the driver's side strut tower.	NX supplies you with a full arrangement of fittings to do the job.
Our Steeda high-flow fuel rail had a 1/8-inch NPT fitting already in the side of it, which can be used for nitrous or for a fuel gauge. This was the perfect place for our 4-AN fuel enrichment line.	The NX kit comes with a full array of nitrous oxide and fuel jets so you can alter the amount of power you wish to add.	In order to achieve the 75hp setting, we used the #41 jet for the nitrous and the #22 jet for the fuel enrichment. Both jets get mounted on the NX Shark nozzle and are held in position by the braided 3-AN lines.
Our full-throttle switch didn't match well with the throttle body linkage so we elected to simplify the problem with a cockpit-mounted button. We routed the red wire from the relay (under the hood) to the button and then connected it to a key on/engine off fuse at the fuse box. We didn't want to resort to drilling holes in our new console to mount the switch, so we temporarily taped it to the parking brake handle, which worked out well. Eventually, we'll find a cleaner location for the button, preferably on the steering wheel.	Here is the Focus with its new NX 75-shot Stage 1 system armed and ready. Our on-track results were both shocking and unexpected to say the least. Make sure to mount the solenoids in an area that will keep them away from heat and never arm the system at low-engine rpm or when the car is not running. This will result in a severe engine backfire.	The NX kit also comes with an installation instruction manual to ease the installation process and the wiring diagram cannot be any easier. The green wire from the relay activates the two solenoids, the white wire gets grounded, the black wire is your constant positive (battery) source and the red wire gets routed to the activation switch or button. It's that easy.