We are all fans of big American V8’s here at powerTV, but the future does not seem too friendly for big-displacement monoliths like American muscle car owners are used to. Where once over 90% of cars sold in this country came with a V8, now just a fraction of those sales have more than six cylinders. Even GM is getting in on the low-displacement action as crosstown rivals Ford push hard for customer acceptance of their small, turbocharged EcoBoost engine.

The General will be responding in kind, according to rumors from GM Inside News. A 2.0 liter turbo is supposedly in the works for the upcoming Cadillac ATS.

This is not to be confused with the current 2.0 liter four-cylinder found in the Buick Regal Turbo, which in the Regal GS makes 270 ft-lbs of torque and 280 horsepower. The new EcoTec 2.0 liter turbo will debut in the ATS in 2012, and it will serve as a V6 replacement in both the ATS and the Malibu sedan.

Rumor also has it that GM is working on a twin-turbo V6 engine as well, as a performance V8 replacement, also to debut in the ATS in coming years. But GM has also said that its mid-size sedans will be ditching V6 engines altogether. This may not seem like welcome news for V8 engines, but consider this; if most of GM’s vehicles use fuel-efficient four-cylinder engines (with turbos!) that will leave GM with more wiggle room when it comes to equipping other vehicles with V8’s. At least, we hope.