What does the future hold for supercars with new fuel economy rules?

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As the 2009 Corvette ZR1 was unveiled on the very same day that President Bush signed into law a new energy bill, the obvious question is where do we go from here? The most prominent part of the bill was the first increase in corporate average fuel economy requirements in over two decades. By 2020, most manufacturers will have to achieve a sales weighted average fuel economy of 35 mpg for their fleets. Note that was "most" and not "all" manufacturers, a subject we'll return to in a moment.

At the press preview of the new LS9 engine, GM Powertrain VP Tom Stephens was asked about gas guzzler taxes and how the energy bill would affect the future of cars like the ZR1. Stephens acknowledged that the ZR1 would have a gas guzzler tax, although the final mileage numbers weren't done yet. As for the future, it's too early to tell. In the past, the death of performance cars has been predicted repeatedly and here we are at a new high water mark. Corvette VLE Tom Wallace said at the car's debut that the ZR1 would last at least through the C6 model cycle. No decisions have been made about the C7 and beyond. Keep reading after the jump.

Aside from the Corvette, the question actually gets more complicated for other manufacturers. The fuel economy rules actually exempt or grant waivers to manufacturers that produce fewer than 10,000 vehicles annually worldwide. So Ferrari, Lamborghini and Lotus are safe. The trouble comes for the likes of Porsche, Mercedes-Benz and BMW, which produce far more vehicles. The latter two at least can balance some of their AMG and M models against smaller more efficient cars. Porsche has no such option, which may be part of why it is taking control of Volkswagen.

In order to get the low volume exemption, the manufacturer has to be a separate corporate entity, which rules out spinning off Corvette as a separate brand from Chevrolet. It all gets lumped together under GM. On the other hand, being part of a large company like GM actually gives the Corvette an advantage compared at least to the German companies. Because the fleet economy numbers are based on a sales weighted average, and the Corvette volumes are relatively small in comparison to overall GM sales, the sports car actually doesn't sway the numbers that much.

It's entirely possible that in the coming years we might see AMG and M spun off from their parents and classed as low volume builders. With technologies like dual clutch transmissions, direct injection, biofuels and some sort of hybrid setup, it's also distinctly possible that enough progress will come that future generations of ZR1, Viper and Carrera will play happily on the back roads with Tesla Roadsters. The absolute truth is that it's anybody's guess what the future holds. But if the past is anything to go by, it won't be what you expect today.