The California Air Resources Board (best known by its catchy acronym C.A.R.B.) has been regarded by many enthusiasts as the bane of their existence. After all, what good could come of a group of pointy-headed environmental activist liberal bureaucrats cloistered in an ivory tower in Sacramento?

Well, it could be said that they can take some of the credit for the demonstrably cleaner air in the greater L.A. area. This despite an exponential increase in the number of vehicles and population since the 1970s, widely regarded as the nadir of air quality for the region. Those of us born before the Reagan administration remember the dark early days of smog control, with engines choked by restrictive pellet-bed catalytic converters, unreliable electronically-controlled carburetors, and laughably anemic outputs of large-displacement engines. (Say, a pulse-pounding 160 horsepower for a 350 cubic-inch V-8?)

Left-coast enthusiasts rightfully cursed the heavy-handed bureaucracy for forcing the hands of the automakers, and seeing power outputs cut in half nearly overnight. But after the automakers whined about the "impossibly strict" regulations, and finally pulled their collective minds out of the stone age, they figured out how to give enthusiasts the best of all three worlds, economy, performance and clean emissions. Evidence? The 400-horsepower LS2 V-8 rivals the output of any 60s-era musclecar (when using modern power measurment standards) and gets nearly 30 miles per gallon in the Corvette. 25 years ago, if you would have asserted that a 365 cubic-inch engine would produce 400 horsepower, pass smog with flying colors and get almost 30 miles per gallon, you'd be committed to a mental institution. The idea of a normally-aspirated engine producing more than 100 horsepower per liter also was considered the domain of purpose-built race cars not long ago. Yet Honda now routinely produces such engines in production vehicles.
 
In some ways, we're seing history repeat itself with the new-generation of clean diesels. The OEs are clamoring to get these thrifty, fun-to-drive models to market, but now have to contend with new emissions regulations that don't differentiate between gas and diesel, meaning that diesels have to be just as clean as equivalent gasoline models. The conundrum is two-fold. Firstly, American diesel fuel, up until recently, had a relatively high sulfur allowance. In the ballpark of more than 500 parts per million. Even at 500 ppm, the fuel is considered "Low Sulfur." Soon to be mandated is ultra-low sulfur diesel, which only allows for a minute 15 ppm. Eliminating sulfur in the fuel will allow for the use of more diesel catalyst technologies. The reason Europe has seen rapid and prolific development of diesels over the past few years, and we've seen virtually none other than 3/4 and 1-ton trucks, is that the overriding concern of European regulators is carbon dioxide output, whereas C.A.R.B. and the EPA look at particulates (soot), NOx and a variety of other pollutants.

So the OEs are now having to design for an entirely new set of standards. The proposed solutions on the table in some ways mirror the clunky measures adopted in the 1980s. DaimlerChrysler is awaiting regulatory approval on a urea-injection catalyst system. The EPA and C.A.R.B. have rightfully asked "So what do you do when it runs out?" But seeing as a full reservoir of the stuff should last upward of 6,000 miles, topping off the tank will likely become as routine as changing the oil. The other is essentially a "blast-furnace" catalyst that traps particulates, and then obliterates them with thousands of degrees of heat. As odd and Goldbergian as these measures seem now, I'm sure in a few years, much more elegant and integrated solutions will be implemented, and the early days of the "new diesel" will be but another interesting chapter of automotive technological evolution.