2011 Kia Optima Hybrid - CNET
Kia reuses the 2. 4-liter engine block from the standard Optima in its hybrid, but makes a few changes to the head. We, at first, scoffed at this perceived aspirational downgrade, but Kia's engineers tell us that when combined with the electric motor, the Atkinson cycle proved to be as efficient as the direct-injection setup, and was also less expensive for the... Working in tandem with the gasoline engine is Kia's hybrid electrification system, a doughnut-shaped electric motor and generator that sits between the engine and the six-speed automatic transmission. The motor is able to accelerate the vehicle from a stop under pure electric energy--and usually does so up to about 18 mph to 20 mph. Once up to speed, the motor can also provide electric assist, boosting the power of the gasoline engine, or allow the vehicle to cruise for periods in EV mode. We were surprised to look down at the instrument cluster and see the Optima occasionally illuminate the EV mode light at upward of 70 mph (on a slight downgrade, of course) despite the fact that Kia's materials state an EV cap of 62 mph. Of course, when it's not motivating the vehicle, the motor can also act as a generator, sending power back to the battery pack through regenerative braking. Source: www.cnet.com
