Spied: GM begins testing turbo four-cylinder engine in large cars

Spies in Sweden snapped photos of a prototype that appears to be a next-generation Buick LaCrosse, but there's more going on here than meets the eye. According to a check of the prototype's license plate information, the car is registered to Saab and was built by Holden. The car is also listed as having a 260 hp engine four-cylinder -- the type GM officials have hinted might show up in the Pontiac G8 and other large cars.

GM vice chairman Bob Lutz told Leftlane that such a model was under development at the 2008 New York Auto Show, and these photos appear to be confirmation. According to the car's wrap sheet, it's powered by a 260 horsepower engine and weighs about 300 pounds less than the Pontiac G8 GT.

Lutz indicated that the Holden-derived Chinese market Buick Park Avenue would also be powered by the same 260 horsepower 2.0L turbo four found in the Pontiac Solstice GXP, Saturn Sky Red Line, Chevrolet HHR SS and Cobalt SS, due to China's graduated taxation system which drastically increases on engines larger than 2.0L.

Despite the engine being in a car that is "seemingly way too big," Lutz says the engine "[feels] just great."

The combination of the smaller displacement engine -- which is a third of the size of the Pontiac GT's 6.0L V8 -- and lighter curb weight could see the these sedans post fuel economy numbers in the low 30s.

With ever-rising fuel prices and stricter CAFE regulations, it might not be long until we see a four-cylinder powered G8 on our shores.

April 24, 2008