DETROIT -- Honda ditched its long-running Integrated Motor Assist hybrid drive system and took a page from the Toyota and Ford engineering playbooks with the 2014 Accord Hybrid.
The result: The Accord Hybrid becomes the first mid-sized family sedan to receive an EPA rating of 50 mpg in city driving. That, and the car's 45 mpg highway/47 combined, puts a version of Honda's bread-and-butter car right in the mid-sized family sedan fuel economy race along with the Camry, Fusion and Volkswagen Jetta hybrids.
That 50 mpg EPA city rating of the 2014 Accord Hybrid, announced late last week, more than doubles the city EPA rating of the last Accord Hybrid, which got only 24 mpg in 2007.
Doubling that rating comes mostly from Honda adopting the same basic technology -- an Atkinson cycle gasoline engine and a more efficient electric drive system -- as Toyota and Ford. Honda's new hybrid drive system is part of the company's Earth Dreams technology.
An Atkinson cycle engine keeps intake valves open briefly during the compression stroke, which pushes some of the air into the intake manifold and lowers the compression ratio. The result is lower power output but more efficient combustion at lower speeds. The hybrid powertrain's electric motor makes up for the lower power output of the engine.
The new Accord Hybrid also uses lithium ion batteries, which are lighter and more powerful than the nickel-metal hydride batteries used in the last Accord Hybrid. The other big change is a second electric motor in the Accord's transaxle.
Honda still uses its old-style hybrid powertain in the Civic Hybrid, which is EPA rated at 44 mpg city/44 highway/44 combined. A Honda spokesman would not say if the Civic Hybrid will get a hybrid powertrain similar to the Accord.
Honda began building the Accord Hybrid at its Marysville, Ohio, plant on Friday, Sept. 6. The car is expected to arrive at dealers this fall; pricing has not been announced. The 2014 model is the first Accord Hybrid to be built in the United States.