Improving Aerodynamics with Challenger Chin Spoilers & Rear Diffusers

Before discussing how to handle the issue, we must identify what we’re up against. Drag coefficient is a measurement used to identify the resistance of an object in a fluid environment. Seeing as the Challenger is no submarine, the fluid environment it faces is air. The drag coefficient of the Challenger is a number that tells you how well the car cuts through the air at speed.

The Challenger has a big flat front end. When faced against the wind, it cuts through the air about as well as a paddle cuts through water. The ’08-’14 Challenger’s CD (Coefficient of Drag) is measured at 0.353 while the ’15-’18 is measured at 0.356. To put this into perspective, we need to compare it to other vehicles. 

Cars that cut through the air best will have a CD closer to zero while vehicles that don’t will have a higher value CD. For perspective, the 1969 Daytona Charger’s CD is measured at 0.28 while a 2015 Ram 1500’s CD is measured at 0.36.

With the Challenger sitting next to a Ram 1500 in terms of aerodynamics, things are looking pretty grim for owners of the modern muscle car. Improving aerodynamics is beneficial on multiple fronts. Improved aerodynamics means the car will have to work less as hard to get up to speed and will stay stable at high speeds.

Speed: The reason most Challenger owners will improve their car's aerodynamics is to help the car get up to, and maintain, high speeds. By cutting through the air, the engine will have less trouble pushing the car through the air and up to speed; this ultimately means the car can move faster in a forward motion.

Economy: With less resistance, the engine will not have a much strain on it. At lower speeds, the CD stacks up as slightly less but residual gains will be had. With the engine working less hard, not as much fuel will need to be burned. This means that some minor gains in fuel economy can be had with economy driving.

Some wacky aftermarket kits have been produced to make Challengers appear like Daytona Chargers. Though functional, it’s likely that most won’t reach for these wild body kits. This means very little can, and will be, done to reshape the face of the Challenger.

To increase aerodynamics, one doesn’t need to bring the front end to a point. Chin spoilers can be added to help the car cut through the wind while diffusers can be added to keep the air flowing turbulent-free through the rear.

Chin Spoilers: Fitted to the front of the car below the grille, chin spoilers work to help the car cut through the air with ease. As the Challenger travels forward, air pressure builds up under the car. This pressure works as a force that pushes the car upward. Chin spoilers work to prevent this by redirecting the air and reducing how much can build up underneath. This mod gives the car tremendous advantages over its stock form when traveling at high speeds.

Rear diffusers: Air pressure buildup under the car can be reduced with chin spoilers but is unavoidable. Rear diffusers work to reduce the resistance of air flow through the rear of the vehicle. When paired with a chin spoiler, these units work to dramatically reduce the amount of pressure that can build up underneath the vehicle while traveling at high speeds.

Fiberglass and carbon fiber can be used to construct chin spoilers and rear diffusers. The benefit of fiberglass is that it’s cheaper than carbon fiber, but is a bit heavier.

Carbon fibers advantage is the weight savings, but it comes at a high cost. While carbon fiber is lighter, it is more brittle and cracks easier in cold weather.

Installation of chin spoilers and diffusers on Challengers is extremely easy. They take advantage of factory mounting points on both the front and rear bumpers. One will simply have to remove the hardware in these locations and mount the spoiler and diffusers using these locations. The vehicle will need to be lifted in order to install these components so safety measures must be taken. Altogether, one can likely install both a chin spoiler and a diffuser in just over an hour’s time. 

Reverting to Stock: The last thing you will need to consider when installing these components is whether or not you can return it to stock form. Because the vehicle will not need to be altered in any way means that one can easily remove the spoiler or diffuser and replace the factory hardware with no problems whatsoever. 

These components will hang very low to the ground. At first, it will take some getting used to. The ride height of the car is not altered but parts of it are now closer to the ground. 

While driving, be mindful of the components while approaching speed bumps and curbs. If these parts become cracked or damaged, it can impede their abilities to deflect and increase airflow rendering them nearly useless.