Why Do Some Cars Have Small Vents On The Sides Of The Front Bumper?

Cars like the Chrysler Airflow and Tatra 77 really pioneered the use of aerodynamics in the automotive world way back in the 1930s. Since then, the technology has really exploded, with developments such as active aerodynamics appearing on the latest 911 Turbo S, and other swanky supercars, allowing them to hit immense speeds on the straights, without compromising cornering agility. However, the mass majority of us don't drive supercars, or 1930s Chryslers for that matter — but that doesn't mean more typical cars don't also benefit from impressive aero-based tech.

You may have noticed small vents, or cutouts, on the front bumper of cars like the Ford Mustang – which we reviewed and loved – or even some EVs, like the electrified Porsche Macan. These vents are more than just stylistic features, and they aren't for cooling either. Rather, these cutouts are what's known as air curtains. Air curtains allow air to be channeled through the bumper and into the front wheel wells, thus reducing the air resistance on the vehicle.

Air curtains serve a number of invaluable purposes, and they're likely more beneficial than you'd first think. First and foremost, reducing air resistance will help to improve fuel economy. Regardless of whether you drive a 5.0-liter Mustang or electrified Porsche, getting more out of your fuel — be it gas or otherwise — is always a welcome benefit. Not only that, but the incorporation of air curtains also improves the driving experience, by reducing noise, vibration, and harshness (NVH). 

Moreover, without air curtains, increased air resistance at the front end will hinder a car's performance, in terms of both acceleration and top speed, as the vehicle has no choice but to force the air out of the way, without giving it a flowing route to follow. Introducing air curtains allows that air to slip away with minimal intrusion, and less air resistance means more performance. So, while to many those little vents on your bumper might just look like cool little design elements, they actually serve a multitude of purposes, all helping you to get the most out of your car, be it in terms of outright performance, efficiency, or comfort.