It looks like Congress is going to pass a bill to increase the CAFE that President Bush will sign. This legislation will force manufacturers to increase the average fuel economy of their cars to 35 MPG, from the current 27.5 MPG. The increases will be phased in over time, starting in 2011 and completing by 2020. (Light trucks see a similar increase from the current 22.2 MPG.)
The last time the CAFE standards were raised we saw a dramatic reduction in the size and horsepower of almost all passenger cars. Will we see the same thing this time?
Probably not, as the previous increase called for doubling fuel efficiency, while this new standard represents only a 40% increase. Americans keep demanding larger and more powerful cars, too—witness the growth of the Toyota Camry and Honda Accord—in spite of record gas prices. I see a great opportunity for manufacturers to re-use the excellent engineering that has gone into making passenger car diesel engines in Europe to help them meet the new CAFE standards.
For example, Honda's Accord with the i-CTDi diesel engine produces 251 lb-ft of torque at only 2,000 RPM. Compare this with the 3.5L gasoline engine, which produces 250 lb-ft of torque—but only if you crank the engine all the way up to 5,000 RPM. In everyday terms, this means that the diesel engine feels much more powerful from a stop and keeps that powerful feeling throughout the normal driving range. Yes, if you flog both cars the gasoline version is about 1.5 seconds quicker to 60 MPH, but the diesel doesn't feel like an anemic, wheezing four-banger during 99% of the average driving experience.
Add to that a fuel economy of about 42 MPG (using American, not Imperial, gallons), compared with the 19/29 MPG (city/highway) of the gasoline V6 version, and I think you'd have a very popular car.