Ugly Aerodynamic Tail Makes For Good Fuel Efficiency


Some people will go to great lengths to get the best gas mileage possible. There are simple ways of doing this of course, like using a light touch on the gas pedal and coasting whenever possible. If you’re mechanically inclined you can retard the timing or even perform an engine swap in pursuit of high MPGs.

Or you can add a hideous duck tail to your geo metro. Hey, whatever works, right?

Forum member MetroMPG, aka Darin Cosgrove, founder of Ecomodder, set the goal of creating a lightweight, easily removable tail to add to his Pontiac Firefly (actually a Geo Metro) to improve the aerodynamics. Improved aerodynamics mean improved fuel efficiency. The tail also had to be easy to disassemble and fit in the trunk of the Metro.

Now the Firefly could best be described as a “bare bones” car, and could easily attain 40 MPG with its Suzuki-sourced 3-cylinder engine by driving gingerly. But it isn’t exactly the most aerodynamic car. But by adding the aluminum, cardboard, and duct tape duck tail, Cosgrove estimates he dropped the drag coefficient from .34 to .23, improving mileage by 15%. He was able to clock in 64 mpg driving at 56 miles per hour. That may sound slow, but I don’t go much faster in my Wrangler because, well… it is a box on wheels and my gas mileage plummets when I go over 60.

While the Firefly isn’t going to win any Concours awards, automakers would be wise to consider improving the aerodynamics of future models. For one, that tail could prove very useful as either a storage hatch, or even better, an engine compartment with the added benefit of improved fuel economy. The Aptera 2e has a similar tail, though gas mileage isn’t so much a concern with an electric car, right?

Would any of you be willing to perform a similar modification to your car to get 60+ miles per gallon? I think I’d rather do an engine swap myself.

Source: EcoModder

Christopher DeMorro

A writer and gearhead who loves all things automotive, from hybrids to HEMIs, can be found wrenching or writing- or else, he's running, because he's one of those crazy people who gets enjoyment from running insane distances.