To understand how nitrous oxide injection impacts the engine, let’s take a look at how an engine works. An engine creates power through the transfer of energy created by the combustion of fuel. Combustion is a form of rapid oxidation, which requires oxygen as the name suggests. The amount of oxygen determines how much fuel can be burned, and the more fuel that is burned, the more energy that is created.
Nitrous oxide is a chemical rich in nitrogen and oxygen. Nitrous oxide injection increases the oxygen density of the intake air. Nitrogen is a cryogenic liquid with a very high vapor pressure. It must be maintained at a minimum of 745 psi to remain liquid at room temperature.
Since the vapor pressure is as high as that of a liquid at room temperature, when nitrous oxide is released into the atmosphere, it undergoes a very rapid expansion as it metamorphoses from a liquid to a gas. There is a large amount of evaporative cooling that takes place as the liquid evaporates, drastically reducing the temperature of the surrounding air.
When this chemical reaction is added to the intake air of a combustion engine, you get the double effect of an oxygen-rich intake charge and supercooled dense air. The higher air density and oxygen percentages allow more fuel to burn, creating large amounts of energy. This cooler air reduces the chances of premature detonation that can damage internal engine components. Just the air cooler alone can increase horsepower by about 5 percent.
As stated above, you must have extra fuel for combustion to occur properly because with a dense, oxygen-rich intake charge, you’ll find yourself running dangerously lean under nitrous oxide injection conditions. To get more fuel, there are several tricks that can be done.
First, you can add an aftermarket fuel pressure regulator for nitrous systems. These regulators will hold the return fuel line under nitrous injection, raising fuel pressure to the injectors, providing more fuel. Others have added a fuel cell, which is a small extra “tank” of fuel, usually filled with racing or higher octane fuel, that will activate and supplement the factory fuel settings to keep the air/fuel ratio in the zone optimal for the maximum amount. of power.
However, you can’t squeeze every ounce of power out of your engine without some pretty major modifications to its internals. On a standard, unmodified engine, it is recommended to stay within a maximum of 40% of your vehicle’s power rating on the number of power shots and keep shots to less than 10 seconds per shot. Any more than this in a stock engine and you could be in big trouble. I know of several cases where more power than recommended was used, only sacrificing burnt rings or a burnt intake manifold.
There are several types of systems such as smooth street setups, dry single point injection, wet single point injection, direct port injection, and two-stage race applications. Be careful when selecting which one to use and make sure you balance it correctly with air and fuel. Keep the pedal to the floor and stay TUNED!
