Fuel efficiency and horsepower
From what I've seen, high performance cars like Ferraris and Lamborghinis have a lower fuel efficiency under normal driving than, say, a Nissan Maxima of the same weight.
Why is this? I know the engines have a higher horsepower output, and under full power, they're burning fuel much faster, but this doesn't explain the inefficiency under normal driving. A Ferrari at 10% throttle is using the same horsepower as a Hyundai Accent at 50% throttle at highway speeds. I would think that equal horsepower = equal fuel consumption.
Is it because of the size of the engines that the fuel has to keep running?
The Corvettes seem to have the best fuel efficiency per horsepower rating, with the ZR1 getting an estimated 23mpg highway from a 638 horsepower engine. Unsubstantiated rumors have it that the SSC Ultimate Aero gets 22mpg highway with a 1183 hp engine.
With this new fuel efficiency legislation being passed in the US at least, it will be interesting seeing what Ferrari can do with their fuel economy numbers. They're bound to impress!