Nifty at Fifty – Ford Mustang
TORONTO – Automotive – The Ford Mustang set sales records in 1964 when the iconic American sporty muscle car was launched. At fifty this year, the Mustang has gone through a lot of changes since those first cars rolled off the assembly line in Detroit.
Today the Mustang is a sleek aerodynamic automobile.
The bold, muscular form of the all-new Ford Mustang reimagines the iconic sports car shape in a way that retains the character that fans expect from the brand while incorporating aerodynamic technology that improves fuel efficiency and performance.
“Even with the classic, forward-leaning shark-bite grille and a more aggressive stance for the new Mustang, the aerodynamics team has made it slice through the air better for increased fuel efficiency while also keeping it planted to the road at higher speeds,” said Dave Pericak, Mustang chief engineer. “The best part is that they met the challenge of creating the sleekest Mustang yet without resorting to a characterless teardrop shape.”
Heading into 2015 Ford Mustang
Design and performance are two of the essential attributes that have made Mustang appeal to millions of fans for five decades. Performance can be improved by increasing the output of the powerplant or reducing the amount of work it has to do. The new Mustang is doing both with improved powertrains and a sleeker shape that slips through the air with less effort.
Aerodynamics plays an increasingly important role in overall vehicle performance as speed increases. The force required to slice through the air goes up exponentially with the speed, so twice the speed requires eight times the horsepower just to overcome drag. That means small changes can have a big impact on both performance and fuel efficiency.
“With the new Mustang, we spent about twice as much time running aerodynamic simulations and doing wind tunnel tests than the previous Mustang,” said Carl Widmann, aerodynamics engineering manager. “Major advances in our computational fluid dynamics capability let us test the effect of design changes and give feedback to the studio in less than 48 hours so they had more opportunity to try out different styling ideas.”
Using air to manage airflow
It’s not visually obvious, but rotating wheels are a major source of aerodynamic drag. However, enclosing the wheels in skirts to smooth the flow just doesn’t look right, especially on a performance car like Mustang. Widmann and the aerodynamics team adopted a different approach for Mustang, giving it the first Ford application of wheel aero curtains.
Vertical slots in the outer edge of the front fascia channel air from the front of the car to openings in the wheel wells, directing it across the outer surface of the wheel and tire. The wall of high-speed air works much like a skirt to reduce drag while still leaving the beautifully designed alloy wheels fully exposed.
Managing temperatures
In addition to helping define the visual identity of a car like Mustang, the grille also has to provide an inlet for air that cools the engine. Allowing air to flow through the engine bay instead of directing it around the sides and over the top of the body increases drag. Each of Mustang’s three available engines gets a unique grille that allows in only as much air as that powerplant needs.
Active grille shutters will help make Mustang powered by the new 2.3-liter EcoBoost® engine even more fuel efficient by further reducing drag at higher speeds when extra cooling capacity is not needed. The shutters can completely close off the grille, sending air over and around the car instead of through the engine compartment. Even the ribs that make up the mesh in the grille have been carefully shaped to reduce air resistance and wind noise.
Keeping the car planted
With a top speed of 155 mph for the V8-powered Mustang GT, ensuring confident and precise handling is crucial. New Mustangs are equipped with splitters and air dams below the front fascia that help to minimize air under the car. Mustang GT also features a pair of vents in the hood that also contribute to keeping the front-end planted on the road.
“We worked closely with the vehicle dynamics engineers that are tuning the chassis to make sure our experimental results for lift correspond to what they feel on the car when driving at the track,” said Widmann. “They provided us with some great feedback that we incorporated into our efforts in the tunnel, and the results are definitely noticeable when driving at high speeds.”
The overall air resistance is a combination of the frontal area and drag coefficient. Despite the wider rear haunches, the lower roofline contributes to a smaller frontal area. Along with a lower drag coefficient, the overall drag force of the new Mustang is slashed by an impressive 3 percent with better roadholding and less wind noise in the cabin. At highway speeds, three percent less drag will return about one percent better fuel efficiency.
