Why Is Engine Size Measured In Liters?

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Long clip ago, horsepower bragging authorities came successful cubic inches. American car ads successful nan '70s screamed "Dodge Charger pinch 426 Hemi" while European engineers measured nan aforesaid point successful cubic centimeters. Then, location betwixt import trading regulations and nan lipid crisis, nan world decided that liters conscionable made much sense.

A liter is simply a portion of measurement for measurement utilized to measurement liquid aliases fluids for illustration gasoline aliases oil. In engine-speak, liters correspond nan full cylinder displacement, which is nan measurement of air-fuel substance an motor tin tie successful during 1 complete cycle. One liter equals 1,000 cubic centimeters, truthful your 2.0-liter four-cylinder engine goes done astir 500 cc of substance per cylinder, springiness aliases return a rounding error. 

In nan precocious 18th century, nan metric strategy was calved successful France and slow dispersed crossed Europe. The U.S., however, clung to nan imperial strategy (which uses quarts alternatively of liters) good into nan 20th century. This metric displacement became applicable for galore industries — including automakers — which caused them to thin into liters for world consistency. Even nan U.S. joined nan nine successful nan precocious 1980s done nan Omnibus Trade and Competitiveness Act of 1988, agreeing to usage nan metric strategy successful weights and measures for waste and acquisition and commerce. Since then, displacement in liters became much than conscionable a spec; it was an identity. A 3.0L V6 sounded soft and powerful, while a 1.3L turbo whispered substance efficiency. Liters became nan lingua franca of performance, precision, and practicality each rolled into 1 neat decimal point.

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Here's nan thing: Engine liters still matter, moreover amidst nan emergence of technology. A bigger motor usually intends much displacement –- much air, much fuel, much power. But acknowledgment to turbocharging and physics substance injection (EFI), that aged norm of thumb is starting to look a small outdated. A modern 1.5-liter turbo three-cylinder tin outgun immoderate 2.4-liter engines from 2 decades ago, each while sipping little substance and making less emissions.

Still, displacement remains useful shorthand for conveyance classification and taxation. Many countries like France, the United Kingdom and Japan taxation cars by motor size, not horsepower. A 1.6L Mini Cooper Coupe might autumn into a friendlier taxation bracket than a 2.5L sedan moreover if nan second is only marginally quicker. And successful nan property of electrical motors, "engine size" is becoming a benignant of automotive shade story. It doesn't mean they will gone immediately, but pinch nan advent of EVs, nan days of liters are dwindling down. There's nary displacement successful an EV — conscionable kilowatts and torque curves that commencement astatine zero RPM. Someday, we'll beryllium bragging astir car specs for illustration "My Tesla Model S has complete 1,000 horsepower. Bet?" 

Don't worry, liters will still beryllium pinch america for a play of time. Give it a decade aliases so, and we'll beryllium telling kids really our cars utilized to respire and tally done cylinders while measuring their capacity successful liters.