How Much Faster Does Nos Make a Car Go

If we can all agree on one thing, it would likely be that horsepower is expensive. What makes it hurt more is the fact that, even when you start with a whole lot, you're still going to crave more. And if you start with very little? Well, you've got a lot of ground to cover to keep up with the modern standard of speed. While the market keeps evolving and more ways to make glorious power are introduced, there has been at least one constant. You can always cram precious gas into virtually any engine to make it go faster in an instant.

We are talking, of course, about installing nitrous oxide—better known as NOS. When NOS is introduced to a combustion chamber, you can instantly stack a staggering amount of horsepower onto your engine. This output increase can range anywhere from 30 to a few hundred additional ponies under the hood.

So, what exactly is nitrous oxide and how does it create power?

Nitrous oxide, also known as N2O consists of two nitrogen atoms and one oxygen atom. When you heat this chemical compound to roughly 570°F (~300°C), the nitrogen and oxygen split. And when you heat this up in an engine, you're upping the amount of oxygen during combustion. As Jalopnik so succinctly points out, "With more oxygen available, you also need to inject more fuel to keep the air-to-fuel ratio optimal, which yields a more powerful explosion, which means more torque to the wheels and thus faster acceleration times. Yay!"

Plus, because nitrous comes out as a cold gas, it significantly cools the intake air, thereby increasing the air's density as well as the amount of oxygen in the chamber—further improving performance.

Installing Nitrous

Heads up: going into this, you should have a moderate to advanced level of understanding of an automobile's operating systems—most importantly fuel delivery and wiring.

The first thing to decide when a installing nitrous oxide system is where you will be mounting the bottle. You want to mount it in a safe place that poses the least amount of risk to the unit. Most people choose the trunk. Although, you can get creative if you'd like.

"The only problem with nitrous oxide is that it is fairly bulky, and the engine needs a lot of it. Like any gas, it takes up a fair amount of space even when compressed into a liquid. Therefore, a car normally carries only a few minutes of nitrous oxide, and the driver uses it very selectively by pushing a button." -HowStuffWorks

Once the bottle's mounting location has been decided, you will need to fasten the bracket to the vehicle. Because this will require drilling, you want to make sure the chosen location offers not just safety but also safe routing for the wiring and plumbing.

Hooking Up to the Engine

Once the bottle is in place, it's time to prep under the hood. Now, this is where the discussion of general NOS installation can become a bit tricky. There are a few variables that come into play. The first is whether you are working with a carbureted or fuel-injected engine. I say this because you are going to have factors to consider on an EFI engine that you wouldn't on a carbureted engine.

Carbureted engines can use universal NOS kits, while an EFI engine needs to use an application-specific kit that taps into the engine's control system with the use of a wiring harness.

Another thing to be aware of is where your additional fuel is coming from. In a wet nitrous kit, you will get a fuel solenoid that opens, to pump supplementary fuel to the engine when the nitrous system is activated. This is usually done by tapping into the existing fuel system and adding secondary lines which will allow for more fuel flow. Though, when a high amount of power is being added by nitrous, a secondary fuel line with a dedicated electric pump is recommended. If the kit is a dry system, you will need to tune the vehicle after it is installed. Otherwise, all that extra oxygen being added isn't worth a damn.

Feeding nitrous oxide to the engine is very straightforward.

For most applications, a spacer is used between the carburetor or throttle body. This spacer is built to accommodate lines from the nitrous bottle.

If you've ever installed a carb or throttle body spacer to an engine, it follows the same procedure just with the additional step of hooking plumbing up to it when you're done. In the case that you're using a custom intake manifold with lines hooking up to each individual runner, you're looking at a basic manifold swap with the same additional step.

Plumbing and Wiring

The necessary plumbing isn't too complex. (Even first timers can get it done with little to no help.) If you're using an application-specific kit for a late-model engine, the fuel solenoid will simply tap into the existing fuel rail. Read through the instructions thoroughly and you'll be just fine. With a carbureted engine using the existing fuel line, your fuel solenoid will tee into the existing feed. Make sure you choose a hookup point where there is enough real estate for the tee to tap in, without interference from other parts of the engine.

Running lines from the nitrous bottle to the engine will be a bit more time-consuming, but this is not due to any level of difficulty. It's mostly because you will be locating a safe route. Once the proper route is selected, you will simply tighten the fittings in place and move onto the wiring.

As I mentioned earlier, wiring is subjected to the application and kit selected.

As a general overview, you'll be running wiring to the interior of the vehicle and to the engine bay to control the system. What this entails is dependent on: whether or not you will be tapping into an existing engine management system, how the system is activated, and whether or not the bottle will be manually or electronically opened. Overall, the steps to a nitrous system's function are: arming, enabling, and then purging the system.

So, this means either two or three switches are typical when installing nitrous. Where you mount them is going to be the most time-consuming part. You can use custom switch panels, find hidden locations in the vehicle, or have a field day and find ways to make them look like original equipment. When the mounting and configuration is decided, all that's left is to run the wiring for each switch to complete the circuit.

Play it Safe

So, with the bottle installed and all the plumbing and wiring in place, you're just about ready to go. But before you head out and blow the tires off, there are a few things to be aware of.

Consider how much power you are adding. This is likely something you are already well-rounded in, but remember that stock internals can only take so much abuse. If your nitrous system has the ability to blow an additional 125 horses on the motor, but your stock bottom end can only take 500, and you're already pushing 450… you might want to consider adding quite a bit less.

This isn't much of a hassle though, as swapping jets in the system is how you control the amount of power added. All you need to do is re-jet the fuel system and nitrous system.

The other thing to consider is timing. Nitrous oxide will increase cylinder pressure. And, for proper and safe performance of the system with your engine, it will require you to adjust the timing by a few degrees. As the smart folks over at Hot Rod Network explain, "For ignition advance, the rule for a mostly street-driven car is to retard total timing 2 to 2.5 degrees per every nitrous-generated 50-hp increase. For example, if you run 32 degrees total now with no power-adder, with a 150-hp nitrous shot, pull the timing back by 6 to 7.5 degrees for a total advance in this case of 24.5 to 26 degrees."

True, there are a fair number of steps involved when installing nitrous. But you're not reinventing the wheel! With the proper experience, this is something you can get done in just a few hours.

How Much Faster Does Nos Make a Car Go

Source: https://www.theengineblock.com/tech-corner-installing-nitrous-a-guide-to-going-fast/#:~:text=We%20are%20talking%2C%20of%20course,additional%20ponies%20under%20the%20hood.

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