Can you guess Which one of these Cars is the Most Aerodynamic?

“Aerodynamic drag has a significant effect on a vehicle’s fuel consumption. This is the reason why fuel-efficient family cars like the Toyota Prius and Honda Insight look so alike (and boring) as their shape is virtually dictated by aerodynamics”. How many times have you heard this? Here at Carscoop, surely more times than we can remember. Even GM’s Vice President, Bob Lutz defended the Volt’s lucklaster design by saying that its styling was aimed at achieving better aerodynamics so as to maximize fuel efficiency. -Continued

Here’s what Lutz said on GM’s official blog: “The vehicle’s design has come under some criticism, most of it, to me, unwarranted. The challenge to the designers wasn’t to design the most beautiful car imaginable and accept the compromises you have to make to do so. It was, make no compromise to fuel efficiency and electric range, and then do the most beautiful design possible, around those aerodynamic dictates.”

While GM has yet to announce a final figure, in a recent interview Lutz said that (currently) the Volt has a Cd of 0.27 to 0.28. There's a possibility that GM may be able to achieve a lower number than that by the time the Volt enters production in 2011, but we’ll have to work with this for now.

Leaving the Volt to rest in piece -figuratively speaking- let’s see the aerodynamic efficiency of the highly acclaimed second-generation Toyota Prius. According to the Japanese brand, one of the most mundane family cars (in terms of styling) ever to be produced has a Cd of 0.26.

Now, how about we take a look at the aerodynamic efficiency of two mid-size sedans that were presented at the Paris Motor Show a few days ago: the Opel Insignia ecoFLEX has a Cd of 0.26 (compared to the standard vehicle’s 0.27) while the Audi A4 TDI Concept ‘e’ has a Cd of 0.25. Oddly enough, neither car looks like a swelled up egg ready to explode...

Both German automakers said that they achieved this by spending many hours in the wind tunnel fine-tuning the design of their production models by adding underbody panels, lowering the suspension etc. Without taking sportscars into account, it goes without saying that there are plenty of other production family cars with a Cd of 0.27 or lower. One example is the beautifully penned 2008 Citroen C5 with a Cd of 0.27.

Even though we’re no experts in aerodynamics, it is clear that that there’s an easy way to achieve a low Cd (Honda Insight, Toyota Prius and Chevy Volt) and then there’s a hard way (Insignia ecoFLEX, A4 Concept e, C5). Of course some cars may be purposely designed to look aerodynamic –that’s a different story. We’re just sick and tired of hearing everybody putting the blame on aerodynamics for a poorly executed design.