Releasing your most expensively developed new model-line should be enough for any company, but not Porsche. While the Panamera grabs the headlines, the company has been busy developing its other models too.

The refreshed Boxster and Cayman were unveiled at the LA Auto Show. Looking just like the images in Planet evo last month, exterior changes are minimal with the big tweaks underneath – new direct-injection engines replace the previous units, with a 255bhp 2.9-litre in the entry-level roadster and a 310bhp 3.4-litre in the Boxster S. The Cayman uses the same powerplants but with an extra 10bhp. Options ape the 911, with the seven-speed PDK double-clutch gearbox, ceramic brakes and a limited-slip diff available. Prices range from $ 45,049 for a Boxster to $ 55,719 for a Cayman S, with sales beginning on February 21.

Spec them with PDK and an official ‘combined’ 9 L/100km is possible. And that figure is matched by perhaps the most unlikely Porsche combination of all – a diesel mud-plugger in the shape of the new Cayenne diesel. At its heart is an Audi-sourced 3-litre V6, with 240bhp and 406lb ft on tap. More key, perhaps, are 9.3 L/100km and 244g/km of CO2 – not bad figures for a two- ton-plus performance 4x4. They’ll be bested by the next branch of the Cayenne tree, however, with a petrol-electric hybrid due by the end of the decade. For now, though, the diesel will set you back $ 60,000, including a Porsche Experience driving day, where you can learn to master your new buy.

What next? Porsche is reportedly on the waiting list for a Tesla Roadster, hinting at a future featuring electric vehicles. (Ruf has already had a stab at a 911-based electric sports car)

Worried Porsche is straying from its roots? Also spotted last month was the next-generation, 998 iteration of the 911. Details are few, but upped performance twinned with slashed consumption and emissions is sure to be on the cards. We’ll have regular updates on its development between now and a 2011 unveil.