The development of direct fuel injection systems has enabled gasoline engines to be more fuel efficient in recent years. Nevertheless, even with the arrival of this technology gas engines are far from being as economical at the pump as hybrid or diesel engines. To reduce the appetites of these gas guzzlers, engineers have been concentrating on the development of new automatic gearboxes that will soon offer nine or even ten speeds. For example, Hyundai is presently working to develop a ten-speed gearbox for its Genesis and Equus models, which already benefit from an eight-speed transmission. In addition, Audi, Bentley, BMW, and Chrysler are all offering models with eight gears. Studies show that these allow gas savings of approximately 11 percent compared to six-speed gearboxes. In the domain of manual transmissions, Porsche has broken ranks in offering a gearbox with seven speeds. For the time being it is unlikely that compact and subcompact cars will come equipped with more than six gears, due to the lack of space under their hoods. This new technology is therefore limited to bigger cars, which explains why smaller car manufacturers are turning towards CVT transmissions (continuously variable transmission). Reliable, light, and compact, this type of transmission offers an infinite number of gear ratios in automatic or semi-automatic mode. Compared with manual gear boxes, most CVTs offer savings at the pump as well as improved acceleration times. The only drawbacks are that they entail an added expense at the time of purchase and some manuf acturers haven’t yet found a way to reduce the amount of engine noise created during acceleration.