Frequently Asked Questions

Will Nitrous affect engine reliability?

The key is choosing the correct H.P. for a given application. A kit that uses the correct factory calibration does not usually cause increased wear. As the energy released in the cylinder increases so do the loads on the various components that must handle them. If the load increases exceed the ability of the components to handle them, added wear takes place. NOS kits are designed for use on demand and only at wide open throttle. Nitrous can be extremely advantageous in that it is only used when you want it, not all the time. All NOS kits are designed for maximum power with reliability for a given application.

Can I simply bolt a nitrous kit onto my stock engine?

Yes. NOS manufactures systems for virtually any stock engine application. The key is to choose the correct kit for a given application; i.e., 4 cyl. engines normally allow an extra 40- 60 HP, 6 cyl. engines usually work great between 75-100 extra HP, small block V8’s (302/350/400cid) can typically accept up to 140 extra HP, and big block V8’s (427-454) might accept from 125-200 extra HP. These suggested ranges provide maximum reliability from most stock engines using cast pistons and cast crank with few or no engine modifications.

What are some of the general rules for even higher HP gains?

Generally, forged aluminum pistons are one of best modifications you can make. Retard ignition timing by 4-8 degrees (1 to 1-1/2 degrees timing retard per 50 HP gain). In many cases a higher flowing fuel pump may be necessary. Higher octane (100+) racing type fuel may be required as well as spark plugs 1 to 2 heat ranges colder than normal with gaps closed to .025"-.030". For gains over 250 HP, other important modifications could be necessary in addition to those mentioned above. These special modifications may include a forged crankshaft, a high quality race type connecting rods, a high output fuel pump dedicated to feeding the additional fuel demands of the nitrous system, and a racing fuel with high specific gravity and an octane rating of 110 or more.

How does nitrous work?

Nitrous oxide is made up of 2 parts nitrogen and 1 part oxygen (36% oxygen by weight). During the combustion process in an engine, at about 572 degrees F, nitrous breaks down and releases oxygen. This extra oxygen creates additional power by allowing more fuel to be burned. Nitrogen acts to buffer, or dampen the increased cylinder pressures helping to control the combustion process. Nitrous also has a tremendous “intercooling” effect by reducing intake charge temperatures by 60 to 75 degrees F.

How much performance improvement can I expect with a nitrous system?

For many applications an improvement from 1 to 3 full seconds and 10 to 15 MPH in the quarter mile can be expected. Factors such as engine size, tires, jetting, gearing, etc. will affect the final results.

How long can I hold the nitrous button down?

It is possible to hold the button down until the bottle is empty. However 15 continuous seconds at a time, or less, is recommended.

When is the best time to use nitrous?

At wide open throttle only (unless a progressive controller is used). Due to the tremendous amount of increased torque, you will generally find best results, traction permitting, at early activation. Nitrous can be safely applied above 2,500 RPM under full throttle conditions.

What kind of testing or research is performed on NOS products?

NOS maintains a complete research and development center including computerized dynamometer equipment as well as a nitrous/fuel flow testing facility. In addition, NOS is actively involved in many aspects of racing: working closely with many top name racers to develop the most powerful and reliable nitrous systems in the world.

How long will the bottle last?

This largely depends on the type of nitrous kit and jetting used. For example, a 125 HP Power Shot kit with a standard 10 lb. capacity bottle will usually offer up to 7 to 10 full quarter-mile passes. For power levels of 250 HP, 3 to 5 full quarter-mile passes may be expected. If nitrous is only used in 2nd and 3rd gears, the number of runs will be more.

Will I have to re-jet my carburetor on my car when adding nitrous?

No! The NOS system is independent of your carburetor and injects its own mixture of fuel and nitrous.

Is nitrous oxide flammable?

Nitrous Oxide by itself is non-flammable. However, the oxygen present in nitrous oxide causes combustion of fuel to take place more rapidly.

Will nitrous oxide cause detonation?

Not directly. Detonation is the result of too little fuel present during combustion (lean) or too low of an octane of fuel. Too much ignition advance also causes detonation. In general, most of our kits engineered for stock type engines will work well with premium type fuels and minimal decreases of ignition timing. In racing application where higher compression ratios are used, resulting in higher cylinder pressures, a higher fuel octane must be used as well as more ignition retard.

Does nitrous oxide raise cylinder pressure and temperatures?

Yes. Due to the ability to burn more fuel, this is exactly why nitrous makes so much power.

Are there any benefits to chilling the nitrous bottle?

No. Chilling the bottle lowers the pressure dramatically and will also lower the flow rate of the nitrous causing a fuel rich condition and reducing power. On cold evenings you might run on the rich side. For optimal running conditions, keep bottle pressure at approximately 900-950 psi. NOS has a nitrous pressure gauge that allows you to monitor this. If you live or operate a nitrous system in colder temperatures, it may also be a good idea to purchase a bottle heater kit, part #14164. Generally, ambient temperatures of 80-90 degrees Fahrenheit will allow for best power potential of NOS kits.

Are there benefits to using nitrous with turbo or super-charger applications?

Absolutely! In turbo applications, turbo lag is completely eliminated with the addition of a nitrous system. In addition, both turbo and superchargers compress the incoming air, thus heating it. With the injection of nitrous, a tremendous intercooling effect reduces intake charge temperatures by 75 degrees or more. Boost is usually increased as well, adding to even more power.

What is the difference between a standard and an NOS Hi-Flo bottle valve?

The orifice of the Hi-Flo valve is much larger than the standard valve allowing for a larger flow of nitrous. With a small orifice valve a pressure drop could occur when nitrous flow is high; causing surging or inadequate nitrous flow. The NOS Hi-Flo valve eliminates this problem. NOS Hi-Flo valves are standard in all NOS kits.

Will the use of nitrous oxide affect the catalytic converter?

No. The increase in oxygen present in the exhaust may actually increase the efficiency of the converter. Since the use of nitrous is normally limited to 10-20 seconds of continuous use, there usually are no appreciable effects. Temperatures are typically well within acceptable standards.

How important is it to use nitrous and fuel filters in a kit?

Some of the most important components of any nitrous system are nitrous and fuel filters. To keep contaminants from attacking the solenoid or plugging up a jet, NOS nitrous filters feature a special stainless steel mesh element from the aerospace industry.

Will I have to change my ignition system?

Most late model ignition systems are well suited for nitrous applications. In some higher HP cases, it may be advisable to look into a high quality high output ignition system with a built in spark retard.

How do I know how much nitrous is left in the bottle?

The most reliable method is to weigh the bottle to determine how many pounds remain. When a bottle is near empty (about 20% or less nitrous remaining) a surging effect is normally felt.