In movies such as The Fast and the Furious nitrous oxide is the magical gas that turns a potent car into a super-fast rocket. In reality, though, nitrous oxide works on a very simple premise and can be fitted to any vehicle. Nitrous oxide was first used in allied fighter planes during the second world war to increase power at high altitude. It is made up of one part nitrogen and two parts oxygen. When heated to about 30c the oxygen and nitrogen separate, so more oxygen is available during combustion.
To make more power in an engine you want to burn as much fuel as possible in as short a time as possible, Nitrous oxide increases the burn rate because there’s extra oxygen in which the fuel can burn. Typically this will boost an engine’s performance by some 30%, reducing its 0-60 time significantly.
Fitting nitrous oxide to your road car is legal, but as with any modification you have to let your insurance company know: The gas is carried in a canister, which is usually fitted in the car’s boot. A pipe is run from the canister to the engine, where it is plumbed into an electrically operated valve on the bulkhead. From here separate pipes take the gas to jets attached to the intake manifold.
Usually there is one jet per cylinder. Inside the car a manually operated switch arms the system. At a pre-determined throttle opening the system is activated and the Nitrous oxide is squirted into the engine.
At the same time a control unit will tell the engine’s management system to add extra amounts of its normal fuel. It is important that the correct amount of extra fuel is added. If too little is added the mixture is oxygen rich, or lean. The leaner the mixture the hotter the cylinder gets, until eventually the piston starts to melt, causing irreparable damage to the engine.
