Nitrous
Nitrous is a power-boosting system used in motorsports that injects nitrous oxide gas (N2O) into an engine to create a temporary but significant increase in horsepower and acceleration.
When racers talk about "nitrous" or "NOS," they're referring to nitrous oxide systems that give engines an instant power boost at the push of a button. The term NOS comes from Nitrous Oxide Systems, Inc., one of the first companies to manufacture these systems for racing applications. Nitrous oxide is stored as a compressed liquid in a special tank mounted somewhere in the vehicle, typically in the trunk or cargo area.
The way nitrous works is surprisingly straightforward. When you inject nitrous oxide into the engine's intake, the heat from the engine causes the N2O molecules to break apart into nitrogen and oxygen. This process releases extra oxygen into the combustion chamber, and since engines need oxygen to burn fuel, having more oxygen available means you can burn more fuel. More fuel burning equals more power.
There's also a cooling benefit that makes nitrous even more effective. As the liquid nitrous oxide transforms into gas inside the intake system, it creates a cooling effect similar to how spray deodorant feels cold on your skin. This cooler, denser air allows even more oxygen and fuel to pack into the engine's cylinders, further increasing the power output.
Drag racing is where you'll most commonly see nitrous oxide systems in action. In these short, straight-line races where every fraction of a second counts, the instant power boost from nitrous can mean the difference between winning and losing. The driver typically activates the nitrous system partway through the race when they need maximum acceleration. Formula Drift competitions also allow nitrous, and some racing series even have specific classes dedicated to nitrous-equipped vehicles.
However, nitrous isn't allowed everywhere. Major racing organizations like Formula 1 and NASCAR have banned its use to maintain competitive balance and control costs. The systems can be expensive to install and maintain, and the nitrous oxide itself must be refilled regularly since each bottle only provides a limited duration of boost depending on how it's used.
One advantage of nitrous systems is their consistency. Unlike turbochargers or superchargers that can be affected by altitude or weather conditions, nitrous systems carry their own oxygen supply, so they work the same whether you're racing at sea level or on a mountain.
Safety is a critical consideration with nitrous oxide systems. Improper installation or use can cause serious engine damage, including blown head gaskets, cracked pistons, or broken connecting rods. The extra power puts tremendous stress on engine components, so many racers strengthen their engines before adding nitrous. Professional installation and careful maintenance are essential for anyone considering a nitrous system.