The L1 name refers to the European concept of a "1-Liter" car, meaning one so efficient it uses no more than 1.0 liters of fuel per 100 kilometers. If you're not particularly metric, that translates to 235 miles per gallon.
VW didn't quite make its mark; the L1 actually uses 1.38 L/100 km, meaning its gas mileage is "only" 170 miles per gallon.
The rear-mounted engine, a 0.8-liter two-cylinder turbocharged diesel, is essentially half of VW's current 1.6-liter TDI turbodiesel engine. It puts out 27 horsepower in Eco mode, which rises to 39 hp in Sport mode, and drives through a 7-speed direct-shift gearbox (DSG) paired with a 14-hp hybrid electric system that switches off the engine as the car comes to a stop.
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