Mythbusters Tests The Porsche 928's Aerodynamics... In Reverse

The Mythbusters crew and Popular Mechanics will test later this month the old claim that the Porsche 928 could go faster if driven backwards. To do so, they flipped a 928's body to face the wrong direction.

Porsche 928 enthusiasts have long questioned whether its design caused enough aerodynamic problems to affect the performance relative to other sports cars. The first 928s suffered from a large frontal area for a sports tourer, and a strangely angled tail that did little to manage the air flowing around the vehicle. At 75 mph, the original 1978 928 was losing 28 hp to drag, a noticeable deficit given its 219-hp engine.

Two years after launch, Porsche added front and rear spoilers to better manage aerodynamics; later models included longer rear sections that improved air flow along with upgraded engines that had more grunt to overcome such losses, topping out at 345 hp by the time production ended in 1995.

Our amateur aerodynamicist guess? Turning a spolier-free 928's tail into a snout creates more drag than it subtracts. We'll find out the answer when the episode airs on Nov. 17. Here's a preview showing some of the extreme makeover:

Photo: Curtis Walker