7 October 2002: We may be in an era when fuel-guzzling is getting a little less politically correct, but General Motors has announced it will will produce a 7.5-liter V-12 engine that will be used in future Cadillac models.

The engine will produce at least 500 hp.

GM also said it would use fuel-saving cylinder deactivation technology, which it calls Displacement on Demand, in all of its pushrod V-6 and V-8 engines in the future.

The technology can improve fuel economy of a vehicle by as much as 10 percent. Cylinder deactivation cuts spark and fuel flow to some cylinders in an engine when power demands are light, such as when the vehicle is cruising at highway speeds.

A similar system used on some American cars during the fuel crisis years of the 70s didn't take on because it led to lumpy performance. But modern computer management systems can deal with such situations much better.