News Summary: Car and trucks have smaller engines

ENGINES DOWNSIZED: More cars and trucks come with smaller engines than ever before. Driving the trend are fuel economy regulations, high gas prices and improvements in four-cylinder engines that make them more appealing.

4-CYLINDER GROWTH: In 2007, only 36 percent of new cars came with four-cylinder motors. But that rose to more than half through May of this year.

FUEL SAVINGS: Americans are using less gasoline. So far this year, gas consumption is down 5 percent, according to government data. The drop is partly because people drive less, but smaller engines are helping. In March, the average mileage of new cars hit a record 24.1 mpg.