We have already discussed ways of getting more oxygen into a motor to create more horsepower through supercharging and turbocharging. There is yet another way to perform this fete without the use of turbines, compressors, or rotating machinery. It is known as Nitrous Oxide. Nitrous oxide systems (NOS) come in the form of a bottle filled with gaseous N2O and an injection delivery system that is actuated by either a button or switch usually installed within the car’s cabin.
Nitrous oxide is a compound that will disassociate or split after it has reached a hot enough temperature. This is accomplished during engine combustion when the oxygen molecule will break away from the nitrogen and combine with gas in the system to create a more powerful explosion. This is somewhat similar to superchargers or turbos in that more oxygen has somehow been added to the system to create more power. However with nitrous the oxygen is not being forcibly compressed like with turbos and superchargers, it is just being injected into the system just as fuel is injected.
Power Gain & Fuel Economy
Nitrous oxide systems usually come in kits according to the power output desired. For example, common nitrous kits include 50, 100, 150, 200, and 250 horsepower shots. You also have a selection between Wet and Dry Kits. Wet kits are nitrous kits that have fuel already mixed in with the nitrous mixture. Dry kits just spray nitrous oxide gas directly into the intake manifold. So wet kits should provide more power than dry kits.
Since nitrous is sprayed for only a maximum of a few minutes at a time, and not used very often by most when driving the effects on gas mileage should be quite negligible. Remember, this modification only provides short bursts of power controlled by the driver through a switch or button in the cockpit. So it is up to the driver’s discretion as to how often and when to use the nitrous.
A major advantage to using Nitrous oxide for additional power is the cooling effect of the Nitrogen molecule. If pure oxygen were injected into the system instead of this mixture, the combustion temperature would be too great and could cause a host of heat related damage inside the engine. However during combustion of nitrous oxide the nitrogen molecule disassociates and then absorbs much of the heat from this reaction, carrying it out through the exhaust system harmlessly.
In addition when Nitrous oxide is injected into the intake manifold directly it has a large cooling effect on the incoming intake air by several tens of degrees Fahrenheit. This has the effect of increasing the density of the incoming air allowing more oxygen from the ambient air to enter the combustion chamber and create more power.
One of the major disadvantages to nitrous is its usable time frame. Nitrous depletes so fast that it is only usable for a few continuous minutes at a time, at which point the bottle needs to be refilled. This is a huge disadvantage to supercharged or turbocharged systems which are run continuously as the motor is operating with no problems or refilling of any kind needed. In addition if too much nitrous for the application is used it may cause damage to the pistons, valves, and exhaust system. So care must be taken to match the appropriate system to what the car is capable of handling.