[from occupied ga]

to direct-injection fuel delivery (e.g., directly injectin the fuel into the combustion chamber), which means we can increase the fuel efficiency of a car as much as 20%!

Diesels do that now, and they are a niche market vehicle. Most people opt for performance over fuel economy given the choice.

[RayChuang88]

Actually, you don't see that many diesel-powered cars in the USA because diesel fuel in the USA contains too high a level of sulfur compounds, which can easily damage fuel-delivery systems and exhaust emission control systems. But with the EPA mandating drastic reductions in sulfur compounds in motor fuels (under 80 parts per million for both gasoline and diesel fuels), we can safely apply the very latest in fuel delivery and exhaust emission control technologies, which will reduce gasoline fuel consumption per car as much as 20% and allow diesel engines to meet the stringent Ultra-Low Emissions Vehicle (ULEV) standard.

Imagine all the new passenger cars switching to direct-injection fuel delivery and minivans, pickup trucks and SUV's all switching to the latest clean-burning diesel engines--we could reduce fuel consumption quite a bit.