We've already seen Porsche evaluating a higher-performance version of the Cayman, rumored to be called the GT4. It would reportedly offer a taste of the thrills of the 911 GT3, but at a lower price.
The coupe appears to have a convertible twin in this Boxster prototype. The biggest giveaway of their possible relationship is the shared front bumper with larger intakes and an extra opening at the tip of the hood. Although, this one lacks the Cayman's big, rear spoiler in favor of a smaller decklid unit.
The good news for fans of shifting for themselves is that this tester is fitted with a manual transmission, according to our spies. Being a prototype, though, there's no guarantee that the gearbox makes it to production. At least in Cayman trim, these higher performance models might use a tuned version of the 3.4-liter flat-six with between 370 and 400 horsepower. Though, an earlier rumor suggested that a turbocharged four-cylinder could sit behind the driver.
Until we know for sure, glance at the gallery to see a Porsche that might try to challenge its big brother.