fueled by nitro

The world’s best drivers, fastest cars and top-performance petroleum are all fueled by nitro — which is not to be confused with nitrous.

The world’s best drivers, fastest cars and top-performance petroleum are all fueled by nitro — which is not to be confused with nitrous.

The word nitro is synonymous with speed because when the chemical compound nitromethane fuels an internal combustion petroleum engine, race car drivers can achieve the world’s fastest speeds on four wheels.

But what is nitro? Is it the same as nitrous? How is it different than gasoline?

On your mark. Get set. Read.

Let’s start by getting something obvious out of the way. Yes, nitro and nitrous both contain the element nitrogen. It’s an essential element to life and exists in all kinds of things — from fireworks to fertilizers, steel, soil and petroleum.

Some drag racers utilize nitrous oxide for a competitive edge. They install liquid-cooled tanks of nitrous oxide to provide a jolting boost of power at a critical point in the race. At the push of a button, the nitrous oxide is electronically injected into the inlet manifold. The nitrous vaporizes and expands, providing a huge boost to the cylinders. Translation: Nitrous oxide doesn’t burn or contain BTUs, so it’s not a fuel additive. Rather, the tank introduces a burst of oxygen that elevates the temperature of the fuel, making it possible to burn gasoline faster. Picture what happens when you blow into a campfire, and you kind of get the idea.

So, that’s nitrous. And it’s worth repeating — nitrous is not “top fuel” nitromethane.

In the world of professional racing, nitromethane is known as top fuel. The big advantage of top fuel is that you can get more power out of every single explosion in the engine. Nitromethane, surprisingly, doesn’t actually provide as much energy as gasoline, but man-oh-man does it burn inside those cylinders. Let’s get a little mathy. Cars typically need about 15 pounds of air to burn one pound of gasoline. With nitromethane, you only need 1.7 pounds of air.

Drag racing motors are big, with an average engine displacement of 8.9 liters. When supercharged, they can produce about 6,000 horsepower. Superchargers force even more air into the combustion chamber and, as we’ve learned, an increase in air means more fuel, and greater horsepower. With a supercharger, dragsters can burn close to one gallon of nitromethane per second!

There’s actually not enough time for all of the nitro to burn off between the time the spark plug fires and the exhaust valve opens, which leaves nitromethane aflame in the exhaust pipe. That's why we see flames shooting out of the exhaust pipe of drag race cars.

Top-fuel dragsters accelerate faster than any other race cars in the world, reaching speeds of 335 miles per hour — thanks to nitromethane