Five of the best alternative fuel race cars

More and more race series are turning to alternative fuels. We look at five successful race cars that stay away from unleaded. This past weekend, the first ever victory by a diesel-fuelled car was recorded in the British Touring Car Championship by SEAT. Though diesel is not a new fuel it is still, despite Audi's efforts at Le Mans, a relatively scarce choice in motorsport. Its continued success is likely to lead to the further proliferation of alternative fuels used in competition. This week we look at five racers that shun unleaded fuel.