It burns cleaner than regular gas, reducing pollution from exhaust.

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Nitrogen is separated from oxygen before combustion, thereby reducing the volume of exhaust gas and making the exhaust easier to treat by preventing the formation of polluting nitrogen oxides.

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One is exhaust gas recirculation, which pumps cooled exhaust back into the engine air intake, lowering the combustion temperature and reducing NOx formation.

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Brawn revealed that the revised exhaust system had been overheating the rear of the car so they had had to adjust it, reducing the benefit.

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