Carbureted V-8 applications most frequently use a plate mounted under the carburetor, which has a spray bar that delivers the additional fuel and the nitrous oxide. A typical plate system uses a pair of 12-volt solenoids to control the release of the additional fuel and the nitrous oxide. The nitrous is plumbed directly to the nitrous solenoid. Fuel is supplied from the fuel supply feed line. Changeable jets control the amount of fuel and nitrous oxide fed to the spray bar.
The electric solenoids can be wired to a momentary push button in the interior of the car. An arming switch controls the power to the system so that it cannot be accidentally activated, as well as a full-throttle switch at the carburetor or throttle position switch.
Nitrous oxide is stored in the bottle under high pressure. A full 10-pound bottle will have approximately 800 to 900 psi at room temperature. At this pressure the nitrous oxide is stored as a liquid. Nitrous bottles must always be mounted at an angle with the outlet facing forward and down. This allows the siphon tube to pick up the liquid from the bottom of the bottle.
Producing more power requires a stronger engine. This is especially true when considering engines injected with nitrous oxide. If your engine is in need of repair, then adding nitrous will not help; in fact, it can make things worse.
Nitrous oxide injection has the capability to produce sudden power with increased combustion pressures and temperatures. This necessitates the addition or improvement of the engine and its support systems. How much nitrous oxide you can add depends on what type of engine you have. If you have a stock V-8 engine and a stock fuel system, you should limit your power increase to a 125hp kit.
Obviously, it's wise to be realistic when considering the amount of power an engine, transmission, and driveline can handle. A strong engine coupled to a weak transmission or differential will obviously deliver a lot of disappointment sooner or later. Even if the engine is equipped with the best ignition and fuel systems, its internal components have to be capable of coping with the increased loadings associated with producing more power. Adding a 300hp nitrous oxide kit to a production small-block Chevrolet will not last long. It's better to be a little conservative and gain greater reliability and longer component life.
One of the most important considerations when using nitrous oxide is the selection of a top-notch fuel system. A lack of fuel is the quickest way to damage a nitrous-injected engine. Starved of the necessary fuel, combustion temperatures will soar. Extreme temperatures cause catastrophic damage to pistons and other parts in the combustion chamber and lead to massive engine failures.
To prevent this, the fuel system must be able to handle both the normal engine requirements as well as the additional demands created by the nitrous system. You must immediately upgrade the fuel system if there's the slightest hint that the fuel supply is insufficient.
There are two options available to remedy the situation. One solution is to beef-up the existing fuel system. The preferred method, though, is to have two independent fuel systems: one that serves the engine and another dedicated solely to the supply of fuel for the nitrous system. This is ideal because it protects the engine from spikes in pressure-an undesirable characteristic that can occur when using nitrous oxide. Additionally, this will allow you to make the flow test of the fuel system easier.
Note that the fuel supply (pressure and volume) must be checked at wide-open throttle, since you may have plenty of fuel pressure at idle, but at speed, with the button pushed, pressure could drop dramatically. (Remember, fuel pressure and volume are NOT the same!)