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What is a NOS Car? Pros and Cons of Nitrous

NOS cars | Indy Auto Man, IN

NOS Cars: Does Nitrous Oxide Help Engine or Destroy It?

Most stereotypes about nitrous oxide are cinematic in origin. NOS cars almost fall apart into pieces only in the movies. Most of what the majority think about this gas is just a myth. But what is NOS in a car, and is it a blessing for it? Let’s figure it out.

Nitrous oxide in a bottle is a non-flammable pressurized liquid. It was used during World War II for military aircraft to provide additional power at high altitudes. Nitrous oxide has been used in medicine since the 19th century as an anesthetic. In 1912, nitrous oxide was first used for tuning, and massive gas use to boost aircraft engines was recorded. Car engine boost systems appeared as tuning packages in the late 1970s.

How Much Faster Does NOS Make a Car Go?

does nitrous destroy engines

NOS can increase engine power from 1 hp to several hundred, depending on vehicle performance and modifications.

The nitrous is pumped through a solenoid valve and a nozzle directly into the cylinder or into the intake manifold. When nitrous enters the nozzle, it turns into a gas, 36% of which is oxygen. The nitrous oxide changes from liquid to gaseous, which cools the air in the system and allows more oxygen to enter the engine. As the nitrous oxide heats up and ignites, more oxygen is released, so the engine needs more fuel (air + gasoline = power).

Does Nitrous Destroy Engines?

For most cars, a small dose of nitrogen is enough to boost up to 50 horsepower (depending on the engine). If you want to increase power by more than 50 hp, pay attention to the technical condition of the main engine parts. Pistons, cylinder heads, connecting rods, gaskets, and bolts may need to be replaced. If you want to find out whether your clutch and transmission can withstand the additional load, make an appointment at our service center for diagnostics .

Engine damage can occur if it is not in good condition. The maximum amount of nitrogen used depends on the modifications and manipulations made to the engine to improve its performance. You need to use quality fuel, good spark plugs, and oil, and also tighten all mounting bolts to minimize damage. The nitrous oxide system is not the best way to affect the condition of the clutch and gearbox, increasing their wear. Damage to the catalytic converter can occur if the fuel is not completely burned but remains in the converter.

As specialists, we do not recommend making such changes, because they increase the risk of engine wear.

What to Pay Attention to When Tuning a NOS Car

  • You should not install a nitrogen accelerator on cars that have problems with the suspension and wheels.
  • If you hear abnormal noise, turn off the nitrous oxide system immediately.
  • Do not start the accelerator when the tachometer needle has reached the red zone. The rev-limiter will trip, cutting off the fuel supply and possibly losing the spark. As a result, the engine may be damaged.
  • Start with a slight acceleration and gradually increase the speed so that the driver and the car can get used to the new conditions.

Types of Nitrous Systems

types of nitrous systems on cars

Many manufacturers today, such as Holley (NOS), ZEX, and NX produce nitrous oxide. However, the most famous brand is NOS. Most people use this term when talking about the nitrous oxide system.

Wet System

The nitrous is mixed with fuel in the intake manifold. On carburized cars, it is supplied through the intake manifold plate. On vehicles with a fuel injection system – between the manifold and the throttle valve. The amount of nitrogen and gasoline is dosed for the correct proportion of the mixture.

Direct Injection System

A mixture of nitrogen and gasoline is sprayed directly into the cylinders, allowing each cylinder to take the right amount for optimal performance. The direct injection system also allows you to adjust the degree of nitrogen supply. It is divided into several stages.

At low speed (to reduce wheel slip), you can select a stage with a small nitrogen supply, and for acceleration, increase the amount. The most advanced version of the direct intake system provides the nitrogen supply on the rise.

Dry System

Nitrous oxide is fed through the nozzle into the manifold (only nitrogen passes through it), and fuel is delivered through the fuel injectors when nitrogen is already inside.

The nitrous oxide installation kit consists of:

  • Nitrogen bottle
  • Braided or silicone wires
  • Inlet and outlet nuts, cock and adapters
  • Nozzles (various sizes)
  • Distribution block (optional)
  • Solenoids (fuel and nitrogen)
  • Start buttons

Nitrous Oxide Plant: Which Car Can Be NOS Upgraded?

You can install nitrous oxide almost on any car. A nitrous oxide system is preferable for carburized engines and those that have a throttle valve. In some cases, it will be necessary to do tuning or reprogramming of the control unit to ensure the normal operation of the nitrous oxide. Sometimes you can get it by tuning the fuel system.

There are two types of nitrous oxide systems available today:

  • Automatic. It turns on when the engine accelerates to a certain speed.
  • Manual. The manual system has to be controlled by the driver.

You can also install a mixed system that works in manual and automatic modes.

Nitrous oxide can be installed on diesel motors, engines with a mechanical supercharger, and a turbocharger. Typically, the entire installation takes 5 to 7 hours.

NOS Cars Gas Consumption

It is impossible to say how much a nitrogen cylinder will last. It all depends on how often the accelerator is started and what nitrogen supply is set.

Don’t turn on the accelerator for more than 10-15 seconds. Otherwise, the engine may fail. Furthermore, it is advisable to run the nitrous oxide system at high speed (suitable gear) when the engine is running at a low load and ready for acceleration. You need to choose and configure the system carefully to avoid trouble.

Warning : nitrous oxide, intended for cars, has a specific smell – this is hydrogen sulfide, which is released when the accelerator is started. It is dangerous to human health, so it is strongly recommended not to inhale it.

Are Nos Engines Illegal?

No law in Indiana prohibits the use of NOS boosters on public roads. However, some insurance companies do not accept cars with nitrogen boosters. In this regard, make sure that you can insure the vehicle, and only then install a nitrous oxide system. If you dare and install it, stick a warning sign on the car informing others that there is nitrous oxide in the car.

What Are the Pros and Cons of the Nitrogen Accelerator?


  • Relatively short installation time.
  • When the system is not active, the vehicle can be used normally while reducing fuel consumption.


  • Overuse of the accelerator can damage the engine, transmission, and clutch.
  • The system takes up a lot of space in the trunk.
  • Cylinders with compressed nitrogen are explosive.

As you see, such upgrades may cause more problems than help you quench your thirst for speed. If you are looking for more power, visit Indy Auto Man for a test drive and buy one of the used muscle cars from our car lot in Indianapolis .