LOS ANGELES – Two months after Porsche began producing the third-generation Boxster mid-engine roadster at a Volkswagen Group plant in Osnabruck, Germany, the Stuttgart auto maker unveils the Boxster’s hardtop siblings, the Cayman and Cayman S.

The third-generation coupes, enjoying their world premieres at the auto show here, go on sale in spring, starting at $52,600 for the Cayman and $63,800 for the Cayman S, excluding a $950 destination charge.

Despite its entry-level positioning for the Porsche brand, the Cayman has delivered questionable results and arguably has failed to draw younger customers to the brand since its launch. For at least two years, the car has been significantly outsold by the more expensive flagship sports car, the 911, as well as the Panamera sedan and Cayenne cross/utility vehicle.

Through September, the previous-generation Cayman was one of the slowest-selling entries in WardsAuto’s Luxury Sport segment, which includes 12 vehicles such as the Mercedes SL and SLK, BMW Z4, Audi TT and Jaguar XK. The Chevrolet Corvette leads the segment by a wide margin.

A year ago, as both the previous-generation Cayman and Boxster were nearing the end of their production runs, the roadster easily outsold the Cayman.

The new Boxster is enjoying a hearty reception in an improving luxury marketplace, and the new Cayman potentially could carry on some of that momentum. Re-engineered from the ground up, the new 2-seat coupe is lower, longer, lighter, faster and more efficient than the car it replaces.

Power in the base car comes from a 2.7L flat-6-cyl. engine rated at 275 hp at 7,400 rpm (an increase of 10 hp) and 214 lb.-ft. (290 Nm) of torque at 4,500-6,500 rpm. With the Sport Chrono package, Porsche says the Cayman can accelerate from a standstill to 60 mph (97 km/h) in 5.1 seconds.

The Cayman S employs a 3.4L flat-6 that produces 325 hp (5 hp more than before) and 273 lb.-ft. (370 Nm) of torque. With the dual-clutch PDK transmission and Sport Chrono package, the Cayman S sprints from 0-60 mph in 4.4 seconds, the auto maker says.

The engines, carrying over directly from the Boxster and Boxster S, are oriented in front of the rear axle and now integrate gasoline direct injection, improved thermal management and auto stop/start functionality, which combine to boost fuel efficiency 15%.

The PDK is available in both Cayman models, while a 6-speed manual is standard. As it does in the 911 and Boxster, the PDK enables coasting, in which the engine decouples and runs in neutral during light loads. When an “anticipatory” driving style is employed, Porsche says the system can reduce fuel consumption up to 0.43 mpg (1 L/100 km).

The Cayman benefits from a lightweight aluminum and steel body, which helps shave overall curb weight by about 66 lbs. (30 kg).

New features include adaptive cruise control, offered for the first time in the Cayman, as well as a Burmester premium sound system. Optional is Porsche Torque Vectoring, a system that functions alongside electronic stability control to improve steering response in dynamic driving by selectively braking certain wheels.

Porsche also unveils the911 Carrera, which starts at $91,030 and will be available early next year, and the Panamera Platinum Edition, which carries a base price of $80,500 and goes on sale in January.

tmurphy@wardsauto.com