The 2015 kia optima engine Hybrid model is a very efficient choice, combining a 2.4L engine with an electric motor to produce approximately 199 horsepower. The hybrid system is intended to optimise fuel usage, achieving up to 36 mpg in the city and 40 mpg on the interstate. This engine arrangement is ideal for environmentally aware customers who want to save money while still getting the performance they expect from a midsize sedan.