DETROIT - General Motors Corp., the biggest automaker, said yesterday that it plans to start using V-8 engines for large pickup trucks and sport-utility vehicles in 2004 that save fuel by using only half the cylinders during normal driving.
The engines will boost the vehicles' fuel economy 8 percent based on U.S. regulators' test methods and as much as 25 percent in some actual driving conditions, General Motors said in a statement. The automaker plans to increase production from 150,000 in 2004 to almost 1.5 million in 2007.
Automakers face government pressure to improve gas mileage for light trucks. General Motors and DaimlerChrysler AG's 2001 light trucks don't meet U.S. fuel-economy standards, the New York Times reported last week. General Motors' average was 20.6 miles per gallon, DaimlerChrysler's was 20.5 miles and Ford Motor Co. just met the 20.7-mpg standard, the paper said.
The engine technology "will enhance fuel economy without compromising performance or the ability to carry heavy loads," said Sam Winegarden, chief engineer for General Motors' Vortec V-8 engines. "And, because there is no degradation in emissions, this technology will improve overall emissions to the extent that less fuel is consumed."
The engines use all eight cylinders when started, then switch to four during regular driving. The system automatically adjusts the number of cylinders used as a driver accelerates or is carrying a heavy load.