Researching the products of competitors, even to the point of purchasing and then carefully analyzing each piece, is a common practice in the auto industry, especially so at the bleeding edges of performance and technology. Porsche's purchase of a Tesla Roadster is therefore unsurprising, except that it indicates a dissatisfaction with the eRuf 911 recently revealed in concept form.

The move also indicates work on Porsche's own lithium-ion-powered electric vehicle is still at such a nascent stage that it can benefit from such research. What Porsche is likely looking to discern is Tesla's method for keeping performance up in the face of very heavy batteries.

The eRuf 911 built by Ruf and CalMotors, revealed in October, packages an all-electric lithium-ion drivetrain into the shell of a 997 911, and even manages to keep the original six-speed manual, but Porsche insiders are unhappy with the result, reports Edmunds. Why exactly, hasn't been disclosed, but the rather un-911-like performance is a likely culprit. The eRuf's 7-second 0-62mph (100km/h) sprint time, while quite good for a 4,200lb (1,900kg) EV, is still leagues short of even the base Boxster's 5.8-second time.

Packaging more power without seriously increasing weight will be a challenge - one no doubt made somewhat easier by seeing where Tesla's engineers have spent their time.