With the Los Angeles area making up the largest market for Boxsters and Caymans in the U.S., it was fitting that Porsche chose the Los Angeles Auto Show to debut the latest generations of these two-seat sports cars.

As is common with new designs from Porsche, the exterior changes are subtle. In fact, it will be difficult for most consumers to tell the difference between the new models and their predecessors. But there are changes.

The new Boxster features larger air intakes in the grille, and the LED running lights and fog lights are now in a horizontal arrangement. Headlights are also new, with the two-tube style influenced by the Carrera GT. These style changes are also reflected in the new Cayman, which adds revised rear styling, including better-integrated taillights that use LED technology.

Inside, most controls can now be accessed via an easy-to-read, touch-screen display, which is a considerable improvement over the previous generation’s confusing interface. A new Bose audio system is also available.

But most of the changes are noticeable only from behind the wheel. Both Boxster and Cayman benefit from larger, more powerful engines as well as a number of other technical upgrades.

Powering the basic models is a 2.9-liter flat-6 engine producing 255 horsepower in the Boxster, 265 horsepower in the Cayman. The ‘S’ versions of these two sports cars boast a 3.4-liter engine that puts out 310 horsepower in the Boxster, 320 in the Cayman. Both engines qualify these cars as ultra low emission vehicles (ULEV) and not only provide better performance but also achieve improved fuel economy.

Also available on these new models is Porsche’s innovative, double-clutch gearbox. Named Porsche-Doppelkupplungsgetriebe (gladly shortened to PDK), this gearbox actually features two transmissions --one transmission unit handles gears one, three, five and seven as well as reverse, while the other handles gears two, four and six. This setup allows for very fast, smooth gear changes and better fuel economy, and it can reach 60 mph quicker than with the standard 6-speed manual transmission.

In addition to the powertrain updates, the Boxster and Cayman get larger wheels, an upgraded suspension and larger brakes, all designed to provide even better handling than the outgoing versions.

The new Boxster and Cayman will go on sale in Europe in February and will come to American showrooms in March.