Are car drag coefficients a con?
Not so long ago manufacturers use to quote drag coefficients to demonstrate how aerodynamic their cars were. A good example was the Citroen XM, the front end came down below my knees.
Now the majority front end of cars are blunt and look anything but aerodynamic and yet the manufacturers claim fuel efficiency, was the drag coefficient all a con?
Now the majority front end of cars are blunt and look anything but aerodynamic and yet the manufacturers claim fuel efficiency, was the drag coefficient all a con?
Asked on 21 March 2024 by
Answered by
David Ross
Aerodynamics continue to play a significant role in the performance of modern vehicles, but as times have changed there is an increasing focus on emissions and fuel consumption, so manufacturers have tended to communicate more on the efficiency of various powertrains as a means of expressing the credentials of their vehicles.
As an example, cars such as the Mercedes EQS, Tesla Model S and Porsche Taycan all have a drag co-efficient of 0.22 or less, which is even more impressive when you consider that modern cars tend to be larger than their predecessors and have to comply with more strict pedestrian impact regulations. This compares to a Cd figure of 0.28 for the 1989 Citroen XM.
As an example, cars such as the Mercedes EQS, Tesla Model S and Porsche Taycan all have a drag co-efficient of 0.22 or less, which is even more impressive when you consider that modern cars tend to be larger than their predecessors and have to comply with more strict pedestrian impact regulations. This compares to a Cd figure of 0.28 for the 1989 Citroen XM.
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