The gaggle of compact and subcompact cars that achieve 40 mpg may as well become a crowd: General Motors announced today that its 2012 Chevrolet Sonic hatchback and sedan will also get an EPA-estimated 40 mpg highway in some trim levels.
The Sonic can achieves an EPA fuel economy rating of 29/40 mpg (city/highway) when equipped with the optional turbocharged 1.4-liter I-4, and a six-speed manual transmission. According to GM, the engine is rated at 138 hp and 148 lb-ft of torque, and sports a number of tricks – including variable valve timing, a variable-flow oil pump, electric power steering, etc. – to help increase efficiency.
Those numbers are good enough to best the Sonic’s base 1.8-liter four-cylinder engine by 3-5 mpg, despite the fact that the Sonic turbo producesslightly more power--while the 1.4-liter turbo has the same horsepower as the 1.8-liter, it produces 23 more lb-ft of torque. The base 1.8-liter will get 26 city/35 highway mpg with a manual transmission and 25 city/35 highway mpg with an automatic.
With figures like this, the turbo Sonic lands exactly in the middle of the pack of 40-mpg gas-powered cars--at 29 city/40 highway, it equals the Ford Fiesta SFE and loses to the Hyundai Accent and Kia Rio, both of which get one more mile per gallon in the city. It beats its Japanese competition, however, by a bit more: it bests the Toyota Yaris hatchback by 2 mpg highway and the Honda Fit hatch by a staggering 7 mpg while on the freeway.
Source: General Motors