The 2011 Infiniti M officially goes on sale next month, and in addition to boasting higher performance numbers and a sleek new exterior design, the EPA has officially released some relatively impressive fuel economy numbers for the new sedan. Both the six- and eight-cylinder Ms benefit from technologies like continuously variable valve timing, and the M56's 5.6-liter V8 uses direct injection to aid in better performance as well as improved efficiency.

The base M37 with Infiniti's 3.7-liter V6 produces 330 horsepower and 270 pound-feet of torque, and nets 18/26 miles per gallon (city/highway). This represents power increases of 27 hp and eight lb-ft versus the outgoing M35 model, as well as one more mpg in both driving cycles. The all-wheel-drive M37x is rated at 17/24 mpg, increases of one and two mpg over the M35x, respectively.

V8-powered M56s use an all-new 5.6-liter engine, good for 420 hp and 417 lb-ft–meaning the grandaddy M produces a whopping 95 hp and 81 lb-ft more than the previous M45. Rear-drive M56s net 16/25 mpg city/hwy, and the all-wheel drive M56x is rated at 16/23 mpg. Even though this engine is substantially more powerful than the old 4.5-liter V8, Infiniti has still managed to improve overall fuel economy.