A hood scoop is an opening in the hood, which directs air into the engine compartment. This opening is typically shaped as a scoop, which allows the air to be effectively channeled towards the engine. Most modern cars get air from under the front bumper were it is ran through a series of tubing that can cause the air to get up to 50 degrees warmer than the ambient temperature. This warmer air is less dense which means that it will make the engine create less power. Using a hood scoop will cool this air before it is injected into the engine which will increase performance. Some well designed hood scoops will increase the speed and pressure of the air that enters the engine's intake, creating a resonance supercharging effect. This effect is known as ram air and it is only noticeable at very high speeds, which is why it is primarily useful in racing and not ever day vehicles.
The positioning of a hood scoop is extremely crucial to how well it performs. The best area of the hood that provides high pressure air flow is near the rear of the hood in front of the windshield. This spot is the most effective because the curvature of the windshield creates high amounts of pressure in that particular spot. Because of this high pressure zone, some scoops will actually be turned backwards so that the air bounces of the windshield and goes into the engine compartment through the scoop. This backwards style scoop is actually preferred by many because it does not create any drag or worsening in the vehicles aerodynamics.
Installing a hood scoop can be a fairly difficult process because a perfectly centered hole has to be cut in the hood before the scoop can be attached. The hole has to be perfectly straight because if the measurements are off, the scoop can see a major reduction in air flow. Once the hole is cut, the scoop can be secured to the hood by welding it in place or using an adhesive if the scoop is not made out of metal. Installation of a hood scoop can be done at home by someone that is good with their hands and has allot of tools, but most people would take their vehicle to a body shop to get tedious work like this done.
Over the years, aftermarket accessories have became a huge craze in the automobile industry because they allow people to add cool features on their vehicle without spending tons of money or permanently modifying their car. There are many aftermarket hood scoops that can be purchased for a vehicle and installed only for looks. These scoops will typically only attach with an adhesive and don’t require any cutting or drilling. Since these fake scoops don’t actually increase air flow, they won’t increase performance and are only good for increasing the vehicles looks.