After launching 24 variants of the 997-generation Porsche 911 in seven years, the company introduced the 991-generation car last year, and so is back at the start of the whole process. It?s like passing "Go" in Monopoly, except that Porsche collects $200 million. The all-wheel-drive Carrera 4 and 4S?in both coupe and convertible forms?are the...
