(Automotive engineering: Vehicle components, Engine, transmission, and exhaust) An anti-knock agent helps to stop an engine from knocking, making it function more smoothly. ▶ knock
⇒ Car manufacturers are designing cars which can use anti-knock agents other than lead, because of the danger to health. ⇒ Petroleum refiners have added more light hydrocarbon components to their gasoline
mixtures to make up for the loss of lead as an anti-knock additive. ⇒ Bromine is an important ingredient in the manufacture of anti-knock gasoline.
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