 |
 NOS kit PN 5176 comes with...  NOS kit PN 5176 comes with everything for a complete installation. System parts include a pusher pump and hardware to augment the fuel system's capacity. |
 In stock form we made 238...  In stock form we made 238 rwhp--impressive for an OBD-II car. The factory air silencer hides the beautiful LT1 underneath. We'll soon remove the ugly plastic piece to expose the engine to nitrous induction. |
 Before the system was installed...  Before the system was installed in the car, a plug fabricated from aluminum was TIG-welded together. |
 The nitrous nozzle was screwed...  The nitrous nozzle was screwed in and installed into the hole where the stock air silencer connected. |
 With the solenoids and pressure...  With the solenoids and pressure regulator bench assembled, the assembly was trial-fitted to the car, making sure that it would not hinder any underhood accessories. |
 A custom bracket was fabricated...  A custom bracket was fabricated to securely mount the solenoid assembly. Note the simple layout of the system, but don't try to deny its existence. |
Let's play a little game of car-component-free association. It's quite simple: I throw out a few descriptive features of a car, and you identify it. Ready? Full-frame construction, two-door, six-cylinder, turbocharged, and intercooled, produced in limited amounts for a few years. You knew that was a Grand National or Turbo Regal. Here's another one: Four doors, available in only three colors, 350 ci of LT1 power, makes new Mustangs quiver with fear in their tracks, 400-plus horsepower. Did I stump you? You were doing so well up until the last part. You may think there is no such car, but there is; and it could be in your driveway right now. If you are a lucky owner of an Impala SS, you too can have a 400hp family hauler with some help from NOS.
What should we do after all of our favorite bolt-ons have been added? Take the next step perhaps? In this case, Anthony Castorina from Queens, New York, has been doing some performance hunting for his '96 Impala SS of the green-gray metallic hue. After taking delivery of the car he began adding the usual power-augmenting parts that would drop ETs and raise eyebrows. An MTI cold-air induction system, a Hypertech crank pulley, and a chip add some ponies to the mix, while Dynomax mufflers permit a free-flowing path for the exhaust to exit the car. With these minor bolt-ons, his best time on radials is 14.64 at 95 mph. It's quick enough to impress us, considering it is an OBD-II car, but not enough for Mr. Castorina. He felt this was the limit for the factory naturally aspirated combination.
Aside from lifting off the heads or changing the camshaft and intake, he was in search of an easy way to lower his ETs. He gave each option consideration. Supercharging would require a large initial amount of money, but that wouldn't be the end of the costly route. Tuning and living with the cloud of high maintenance over his head nixed that idea. Turbo systems were also deemed too complex and expensive. So, for a fraction of the cost of any of those power adders, nitrous was given the nod.
The benefits of the NOS system make it worth the investment. Its uncomplicated parts layout, ease of installation, and low initial cost make it the obvious choice. Let's take a closer look at how nitrous works and why the NOS system works so well.
One could conjure up images of instant horsepower, cheap initial purchase price, and low maintenance when the "N" word comes to mind. However, your thoughts could also revolve around engine component failure, such as piston damage, blown head gaskets, or other forms of powertrain carnage. With modern nitrous technology we can eat our cake and have it, too. Gone are the days of supertuning to get the extra kick in the pants that you were looking for at the cost of engine longevity. Today we can practically bolt on and go.
All internal-combustion engines consume air and fuel. The horsepower and torque potential of the engine is based on how much air can go into the cylinders for combustion, as long as there is adequate fuel present. Using a supercharger or turbocharger forces more air into the cylinders, making more power, but nitrous uses a different principle.
Nitrous is stored in a bottle as a liquid. Like most gases, when it is compressed, it turns into aqueous form, allowing us to store it safely in the infamous blue bottle. As nitrous is released into the engine, it goes from 1,000 psi to atmospheric pressure, returning to a gaseous state due to the sudden pressure drop. Although there are two nitrogen atoms present for each oxygen atom in each molecule (N20), the nitrogen is not what is actually burned to give the added power, contrary to popular belief. As the engine inhales the nitrous, only the oxygen atom from N2O is used for combustion. Nitrogen is known as a "spectator" atom and simply goes along for the ride, exiting the engine unused. This technically makes nitrous a form of artificial aspiration because there is more oxygen going into the cylinder than the atmosphere can offer.
Dry manifold is the term NOS uses to describe the system's operation. Instead of injecting the nitrous and fuel together at the intake manifold like other kits, only the nitrous is injected so that the manifold is not wet with fuel. Rex Uraki, Tech Consultant at Nitrous Oxide Systems, elaborated for us: "Using this method, the additional fuel is added through the existing fuel injectors. Their flow capacity is increased by raising the rail pressure to approximately 80 psi so that the injectors provide more fuel with the same pulse width. This is accomplished with a NOS regulator valve, which is plumbed with the solenoids. When the solenoids are activated, nitrous is sent from the regulator valve to the fuel-pressure regulator and works against the diaphragm to increase injector rail pressure. This way, nitrous is carried airborne into the cylinder, and the added fuel finally meets it when the combustion process is taking place in the cylinder. The result is a 150-horsepower increase."