NX Nitrous Express automotive nitrous oxide bottle, $10

Many of the things I highlight here at Auctionbandits are 'bread and butter' items that you see on a regular basis and just know to buy from previous experience. But not all of your opportunities will be so easy to spot! Many of your opportunities will depend entirely on how much you have managed to learn about the world you live in. Know more than the next guy, and you'll make the money instead of him!

This little nitrous oxide tank is a perfect example of what I'm talking about. The lengthy description below gives you an idea of how I was able to profit by knowing a bit more about the world around me than most other people do.

Pretty much everyone has at least heard of nitrous oxide. Some people reading this entry will know it from their dentist's office, because dentists have been using nitrous as an anesthetic for many years. Some people reading this may also know that nitrous oxide is very popular among car enthusiasts because it helps cars get going really fast. And that 'get going really fast' application is just what this entry is about, because whoever buys this bottle from me on eBay will drop it into his or her car for just that purpose. In order for this entry to make sense, you have to know just a little about how car engines work and how nitrous oxide affects a car's engine. Only then will it become clear why people use these setups in the first place. So, to start off with this entry, let's start in the most obvious place - the upper atmosphere!

Everyone knows that the higher you go into the atmosphere, the less atmospheric pressure there is, which naturally means there's less air in any given amount of space. That's why mountain climbers have to carry along bottles of extra oxygen, and why the astronauts way up there have to wear pressure suits as well. But.. what about the passengers on an airliner? They're certainly not gasping for breath, are they? Of course not, because even though an airliner may be cruising along way up above 35,000 feet, everyone inside feels fine because the cabin is pressurized to approximate nearly sea level conditions. This is why you could fly in complete comfort right past the climber gasping for breath on the top of Mount Everest. As we'll see, piston engines are much like people when it comes to the availability of air.

All internal combustion engines require some sort of fuel to run, which in our case will be gasoline. In order to burn gasoline, an engine also requires oxygen, which it gets from the air around us. Very importantly, the ratio of fuel to air must be kept within a very narrow range for the engine to operate correctly. This means that you can't just keep dumping the same amount of fuel into an engine as it ascends to high altitude, because the fuel/air ratio will soon be so far out of range that the engine won't be able to operate. So, as an aircraft climbs into the thin air of the upper atmosphere, less fuel must be fed to the engine to maintain the correct air/fuel ratio. This can only mean one thing, which is that an aircraft engine produces less power as it gains altitude. Before the advent of the supercharger, loss of power at altitude was a very serious concern. Without any way to pressurize the air entering their engines at higher altitudes, those old aircraft were gasping for breath at 10,000 feet of altitude, which is well below the altitude they could operate at, if only they had the engine power to get up there.

Superchargers... everyone has certainly heard of the terms supercharger and turbocharger. Although the two differ primarily in how they're driven by the engine (the supercharger is normally driven mechanically by a belt or gears, and the turbocharger is normally driven by exhaust gases,) they're both essentially compressors that pump air into an engine's cylinders at higher than atmospheric pressure. Since they both do essentially the same job, we'll refer to both variants here simply as superchargers.

The fighter and bomber aircraft of WWII were great examples of how a supercharger can benefit an engine operating at high altitude. Those aircraft were able to fly at over 30,000 feet, and since their superchargers were compressing the air entering their engines to nearly sea level pressures, they could produce power that non-supercharged (which are known as 'normally aspirated') engines could only maintain up to several thousand feet of altitude. But why fly way the heck up there, anyway? Well, one benefit of flying really high is the reduced air resistance, because less air means less drag on stuff moving through it.

This reduced drag meant that those old supercharged planes could really move along way up there. The supercharger is what made it possible for the P-51 Mustangs and P-47 Thunderbolts to surpass 450 m.p.h., and the B-29 bombers to surpass 350 m.p.h., at altitudes so barren of oxygen that people can't even breathe without supplemental oxygen. Without superchargers, those planes would've been lumbering along at less than half that speed, and at less than half the altitude. Okay, I realize we should be talking about cars on the ground, not airplanes at 30,000 feet, but bear with me here.

Internal combustion engines are normally classified by their displacement, which is a function of the diameter of the engine's pistons which is known as the bore; the distance the pistons move up and down in their cylinders, which is known as the stroke; and the number of cylinders in the engine. That's where we get terms like "350 cubic inches" and "750 cc" (cc = cubic centimeters.) Those terms indicate the amount of cubic inches or cubic centimeters a given engine displaces. Larger pistons equal more power, longer strokes equal more power, and more cylinders equal more power. One very basic fact about internal combustion engines is that when all other factors are equal, the engine with the larger displacement will produce more power than the engine with the smaller displacement. The "all other factors kept equal" caveat is very important here because there are many variables that can influence an engine's power output. But to keep things straightforward here, when all factors are kept constant except for displacement, larger displacement wins out simply because a greater amount of air and fuel can be processed at a time.

Now, since a supercharger can boost an engine operating at high-altitude to nearly sea level performance, think of what it can do for an engine that's already operating down in the thick sea-level air. Down at street level, a supercharger performs the very handy trick of allowing a small engine to produce the power of a much larger engine, by forcing air into the cylinders under pressure. And since more air means that more fuel can be burned, the end result is more power.

But what does any of this have to do with our little nitrous oxide bottle? All this talk about getting more air into an engine isn't really about the air at all. It's about the oxygen in the air, which an engine needs to burn its fuel. The problem is that air is only about 18% percent oxygen. At first, it would seem that an ideal solution to our problem would be to just inject pure oxygen into the engine, wouldn't it? The problem here is that pure oxygen has the habit of exploding, and when I think of an intake manifold full of pure oxygen, all I can think of is a backfire that would blow an engine apart. There must be a way to get additional oxygen into an engine more safely, and that's where nitrous oxide comes in so handy.

Remember that when an engine sucks in air to help burn the fuel, what it's really after is the oxygen. And we already know that by getting more oxygen into the engine in the form of more air, we can get more power out of the engine. Now, instead of doing all this compressing and supercharging, wouldn't it be nice if we could just enrich the air going into the engine with a safe source of oxygen? That's just what nitrous oxide does when it's injected right into an engine's intake manifold along with the incoming air. The nitrous remains a completely inert and safe gas as it's injected into the manifold and enters the cylinder. But... when the heat from combustion raises the temperature of the nitrous to around 570 degrees Fahrenheit, the nitrogen and oxygen separate, allowing the freed oxygen to mix with the additional fuel (which must be injected along with the nitrous to take advantage of the whole process,) and voilà - a surge of intense power from the engine!

But wait... there's yet another advantage to this process of nitrous oxide injection. Nitrous is injected into the engine's intake manifold as a liquid, where it immediately evaporates into a gas. You may remember from high school science class that liquids absorb heat as they turn into a gas. So, as the liquid nitrous becomes a gas, it actually cools the rest of the incoming air. And this cooling action makes the entire air charge more dense (cold air is denser than hot air,) which means that the engine is getting even more oxygen than it would get without the nitrous injection.

Here's a final point to think about. As opposed to the supercharger, which is (in most cases) always in operation, and can't be turned on and off to suit driving conditions, nitrous oxide is always off, and is only employed at full engine throttle and in very short bursts, like when really quick acceleration is needed. It has to be like this, because an engine that's 'on nitrous' really goes through the stuff, with a bottle like the one in our example lasting for only a few minutes of actual use.

And there's something else to think about here. Certain factors are taken into consideration before an engine is equipped with a supercharger, as in whether the engine is actually capable of handling the extra power that the supercharger will provide. But since nitrous oxide is so quick and easy to install, it's very easy to abuse. Nitrous oxide can add literally hundreds of additional horsepower to an engine's output without any other modifications to the engine whatsoever. And if that engine's not up to task, it can easily self-destruct under the tremendous load. Just something to think about!

As for all the other stuff that comprises an entire nitrous oxide kit, there's really no need to go into it here because the bottle is the most likely component you're likely to encounter at yard sales and flea markets. But you may be wondering why anyone would want to buy just a part from a nitrous oxide kit, like this bottle. It's likely because it's the part that a nitrous user would want to have more than one of. Let's say you're a nitrous junkie who's used up all your nitrous but you aren't ready to call it a day. What do you do? You hook up your spare full bottle, that's what. And... where do you get that spare bottle? Off eBay, of course!

This NX Nitrous Express automotive nitrous oxide bottle sold on eBay for $81.

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