As for your super efficient 300mpg car I'd love to hear about it in more detail.

"It's still the most efficient car on the road," he said.

There has also been a shift to more efficient cars and natural gas.

This position is to help the engine design team to create better fuel efficient cars.

But she is not even thinking about getting a more efficient car.

This made operation of the cars more efficient, and reduced labor costs.

The car industry has done what it was told to; build more fuel efficient cars.

One is the loss of momentum in building more efficient cars.

The 1970 season brought a less efficient car - a good moment for a driver to pack it in.

But the effort toward developing more efficient cars has largely stopped.