A hood scoop is very visible. If you will see a high performance racing car it will be there right in the front on the hood. The visibility is more by accident because for technical reasons the hood scoop is best located where the air pressure is the highest while the car is in motion. And that place happens to be on the hood.
However being so visible they have come to be associated with high performance vehicles and vehicles that wish to appear like high performance vehicles have them for just decorative purposes.
The function of a hood scoop is to capture air and reach it directly to the engine. This cool air leads to better engine performance. How is that? From the normal air intake of the engine the air travels through the engine area and the area being hot the air gets heated too. This hot air is less dense so for a given volume it contains less oxygen. Whereas the air from a hood scoop reaches directly to the engine is relatively cool. Therefore it is denser and contains more oxygen for a given volume. The higher oxygen level improves the combustion and therefore the power deliver and fuel efficiency of the engine gets better.
These improvements are minor for normal street driving but in a racing situation they can be the difference between winning and losing.
The ability of a hood scoop to capture cold ambient air is also useful when air is used to cool the engine as a whole or a component of the engine.
At very high speed the air rams onto the hood scoop and therefore a high pressure is created. This high pressure allows for supercharging of the engine and increases power delivery. Though a ram air intake is meaningful mostly for aircrafts, some high performance cars have used the technology as well.
A useful feature you should consider having if you opt for a hood scoop is a rock guard. This prevents debris from entering the vent meant for air. Under off road conditions this is particularly important.
Hood scoops are available as car after market products and you can buy and install them as easily as car body kits. If you want to take your car to the next level a hood scoop is a great idea.
