The 2013 Cadillac ATS has been an open secret for a while, and now, with its development nearing completion and a Detroit Auto Show debut just weeks away, more information is beginning to come to light.

GM just broke news of the ATS powertrain lineup, and it's becoming clear that the new ATS will come in a wide range of performance flavors.

When the ATS hits the market next fall it will offer a choice of three different engines: a new 2.5-liter in-line four-cylinder, a 3.6-liter V-6, and a new-generation 2.0-liter turbocharged (2.0T) Ecotec four. It's expected that all three engines will be offered with either manual or automatic transmissions.

In an advance presentation to the press this afternoon, GM officials said that the new 2.0T four, which will be built at Spring Hill, Tennessee, will make its debut in the 2013 Cadillac ATS, and will produce 270 horsepower--that’s even more horsepower per liter than the BMW M3, Porsche 911 Carrera GTS, or Lamborghini Aventador.

With a new twin-scroll turbocharger delivering up to 20 psi of boost, the new 2.0T--really the star of the lineup at launch--should also be a step more responsive than GM’s current generation of turbocharged engines. What’s even more impressive is that the engine makes 90 percent of its peak torque from 1,500 to 5,800 rpm; those changes, to us, add some hope that GM's new performance engine for the lineup will have the sort of robustness and responsiveness of BMW's turbocharged fours and sixes.

2013 Cadillac ATS new-generation 2.0T Ecotec engine

2013 Cadillac ATS new-generation 2.0T Ecotec engine

According to GM powertrain officials, the new 2.0T is over 95-percent new compared to the 2.0T engine currently used in the 2012 Buick Regal GS. Breathing has been completely redesigned--it’s in the opposite direction of the current engine compared to the current 2.0T--and it’s been designed to be easily adaptable to both transverse and longitudinal applications. Bore spacing is the same as the current engine (86 cm bore, 86 cm stroke), but it’s physically several inches shorter--thanks in part to a new modular balance-shaft setup and variable oil pump. Otherwise, special attention has been paid to noise and vibration, to make this a luxury-car engine; it gets a noise-deadening cam cover, as well as special vibration-damping fasteners throughout.

The familiar 3.6-liter V-6 is the same engine that’s already offered elsewhere in the Cadillac lineup, in the CTS and SRX for instance, while the 2.5-liter engine is part of GM’s new Ecotec family and built in Tonawanda.

GM will likely reveal power numbers for the other engines, along with full details for the ATS, at the 2012 Detroit Auto Show in a few weeks.

For all of our coverage to date, check out our 2013 Cadillac ATS page here.