The Porsche 911 adds the next logical member of its family to the fold this fall, when the 911 Turbo Cabriolet and Turbo S Cabriolet lose their hardtops at the 2013 Los Angeles Auto Show.

The new Cabriolet models arrive in the year Porsche is celebrating the 50th anniversary of the legendary sports car, and the 40th anniversary of the turbocharged edition.

MORE: Read our 2014 Porsche 911 Turbo first drive

The Cabriolets share the hard-roofed 911 Turbo's 3.8-liter, twin-turbo flat-six engine. In this installation the Turbo generates 520 horsepower, the Turbo S, 560 hp. Porsche estimated the 0-60 mph times for the cars at 3.3 seconds and 3.1 seconds, respectively, picking up a couple tenths of a second over the last generation. The Porsche PDK dual-clutch transmission is standard on the Turbo Cabriolets.

Gas mileage continues to be a strong point: the massively powerful and hefty Cabriolets are estimated at 17/24 miles per gallon.

The Cabriolets wear the same flared bodywork as the Turbo coupes; they're a little more than an inch wider than the normally aspirated car. The convertible top is power-operated, can open or close in about 13 seconds, and can be operated at speeds of up to 30 mph, Porsche says.

Bose audio is standard, with the excellent Burmester setup an option--as are a rearview camera, adaptive cruise control, and speed-limit recognition.

The 911 Turbo Cabriolet is priced from $161,650, the Turbo S Cabriolet from $194,850. Sales begin early next year.


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