Honda's redesigned 2012 Civic comes to market this spring, a long awaited Tune up of the iconic compact line that include sedan and coupe versions, along with two alternative-fuel vehicles: gasoline-electric hybrid and natural-gas-powered sedans. While the natural-gas model will have limited availability and is intended mostly for fleets, the hybrid is a consumer vehicle that anyone can buy. With the remake, the hybrid gets its first lithium-ion battery pack, an upgrade from the nickel-metal-hydride battery that has been used. The new hybrid comes with a larger gasoline engine — a 1.5-liter, four-cylinder — but also boasts improved fuel economy, Honda says. The EPA estimated combined city/highway rating will be 45 mpg, which is up 4 mpg from the previous generation. There's also a new high fuel-efficiency gasoline-only model, the HF sedan, which Honda says will have highway mileage of up to 41 mpg. Under the hood will be a 1.8-liter, four-cylinder engine with 140 horsepower, connected to a five-speed automatic transmission. It will be the most fuel-efficient model in the gasoline-only lineup, and it will come with the same aerodynamic Exterior body design 'that Honda uses on the new Civic hybrid, designed to reduce wind drag. The HF also will have Honda's ECO Assist technology, designed to provide feedback to the driver to encourage a more efficient driving style. In other words, it lets you know if you're driving economically or in a way that uses more fuel, such as punching the accelerator for jackrabbit starts. Regular sedan and coupe models will have the same 1.8-liter engine, but highway fuel economy of 39 mpg. That's still pretty good for a car running on gasoline. The compact segment recently has been getting a spate of new models that can get 40 mpg or better on gasoline only, such as the 2011 Chevrolet Cruze and 2012 Ford Focus. The 40-mpg mark seems to be the new standard for this class. Also in the 2012 Civic lineup will be two performance variants — the Si sedan and coupe. These models trade fuel economy for power and come with a 2.4-liter, four-cylinder engine rated at 200 horsepower and 170 foot-pounds of torque. Standard is a six-speed manual transmission, The Si models are the continuation of a line of Civics popular with the "tuner" crowd, consumers who enjoy spirited driving and who also like to modify their vehicles to suit their personalities and driving styles. With the new Civic Si models, there is a 22 percent increase in torque over the current generation's 2.0-liter, four-cylinder, which has 197 horsepower and 139 foot-pounds of torque. Even with the power boost, though, the new Si models have better fuel economy, Honda says. The EPA highway rating will be 31 mpg, up from 29 for the 2011 models, which have a city rating of 21 mpg. Honda has not released the city mile Civic HF, Sedan, Coupe and Natural Gas • 140 horsepower, 1.8-nter four cylinder engine. • Five-speed automatic transmission. • ECO Assist technology • EPA-estimated HF highway fuel economy: 41 mpg. • EPA-estimated sedan and coupe highway fuel economy: 39 mpg. Civic Hybrid • 110 horsepower, 1.5-:liter four cylinder engine (combined gasoline and electric). • Continuously Variable Transmission. • Lithium-ion battery. • ECO. Assist technology. • EPA-estimated Civic Hybrid city/highway combined fuel economy: 45 mpg. Civic Si 200 horsepower and 170 Ib.-ft., 2.4-liter four-cylinder engine. • Six-speed manual transmission. • EPA-estimated highway fuel economy: 31 mpg. The new Civic hybrid model will have 110 horsepower and a continuously variable automatic transmission. No prices have been announced yet for the new Civic lineup. But the 2011 gasoline models range from $15,605 to $25,490 (plus $750 freight) and the hybrid version from$23,950 to $27,150 Improved Fuel Efficiency