The two major components to a properly functioning engine are air and fuel. Improving the flow of air into your vehicle's engine will improve performance and fuel economy.
Adding a high-performance air filter or intake kit will allow your vehicle to "breathe" better.
Many of the kits are also available in a variety of colors, making them an aesthetic improvement to your vehicle's engine bay. Their easy intallation make these systems a simple, effective upgrade to most cars and trucks.