Porsche would like to double its current sales volume, and to do that, the automaker will need to expand its lineup. The Cajun crossover and 918 are still a year or three away, and we’re always hearing talk of a sub-Boxster roadster or even a baby Panamera being in the cards. But what about a new coupe to take on Maranello’s finest? Autocar claims that such a supercar could be on the way, and it would go toe-to-toe with the Ferrari 458 Italia. The...