GM is pretty serious is making the 2013 Cadillac ATS one of the most competitive models in its segment, and to prove that they mean business, they have just announced that once this compact luxury sedan will premiere in Detroit, a new 2.0-litre 4-cylinder turbo rated at 270 HP (201 kW) and 260 lb-ft. of torque (353 Nm) will also debut in it.
This new direct-injected engine, producing around 135 HP per litre is one of the most power-dense automotive engines, and if you want to know what that means by comparison, GM provided a list with what competitors have achieved on some of their models :
    Audi A4’s 2.0L turbo (105.5 hp/L)
    BMW M3’s V-8 (103.5 hp/L)
    Lexus IS F’s V-8 (83.2 hp/L)
    Mercedes-Benz C250’s 1.8L turbo (111.6 hp/L)     
Don Butler, Cadillac vice president of Global Marketing said that "This engine is the perfect match for the new ATS, which will be a refined performance luxury sedan," "The 2.0T has an exceptionally smooth and responsive power curve that will make the ATS nimble, quick and fun to drive."
Apart from the 270 HP 2.0T unit the 2013 Cadillac ATS will also be offered with a normally aspirated 2.5L 4-cylinder plant and a 3.6L V6 engine.
GM has also published a video which underlines the efforts that were made in order to reduce friction by around 16 percent in the new 2.0T engine.    

Video :

Source: GM