Special Coverage

New York Int’l Auto Show

Hyundai Motor America debuts two variants of its newly launched ’11 Sonata at the New York auto show today, one turbocharged and the other an electric hybrid.

The ’11 Sonata Turbo fills the marque’s performance role, as Hyundai no longer offers a V-6 engine option for the sedan. The 2.0L 4-cyl. engine churns out 274 hp and achieves an estimated 34 mpg (6.9 L/100 km) highway using regular fuel, Hyundai says.

The Turbo also adds direct injection, making it the first Hyundai to use DI and turbocharging. The regular Sonata has a direct-injected 2.4L 4-cyl. as its only engine.

By the end of its current product launch cycle in 2011, Hyundai will have four models on the market with DI engines, with and without a turbocharger. The Genesis Coupe currently offers a turbocharged 4-cyl.

The Sonata Turbo’s 269 lb.-ft. (365 Nm) of torque stretches from 1,800-4,500 rpms, besting the the 2.0T engines in the Buick Regal and Volkswagen Passat. It also exceeds the torque ratings for V-6 engines in the Ford Fusion, Chevy Malibu, Honda Accord and Toyota Camry.

As with the Regal, the Sonata Turbo uses a twin-scroll turbocharger, which, combined with DI, results in “instantaneous power delivery,” Hyundai says. Advantages of a twin-scroll over a single-scroll turbocharger include improved combustion efficiency, lower exhaust temperatures and cooler cylinder temperatures.

The sole transmission for the Sonata Turbo is a Hyundai-designed 6-speed automatic. Four years in the making, the 6-speed has 62 fewer parts and is 26.4 lbs. (12.0 kg) lighter than the auto maker’s 5-speed automatic in the previous Sonata. A manual-shifting option is featured.

Limited grades of the Sonata Turbo have steering-wheel-mounted paddle shifters.

The 2.0L DI turbocharged 4-cyl. is available on the ’11 Sonata’s SE grade, as well.

Also debuting in New York today is the Sonata Hybrid, the Korean auto maker’s first hybrid-electric vehicle to be sold in the U.S. The company pegs fuel economy at 37-39 mpg (6.4/6.0 L/ 100 km) city/highway.

That compares with 41/36 mpg (5.7/6.5 L/100 km) city/highway for the Ford Fusion Hybrid and 33/34 (7.1/6.9 L/100 km) for the Toyota Camry Hybrid.

Hyundai claims the Sonata Hybrid can travel on electric-only at “steady-state” speeds of up to 62 mph (100 km/h). The auto makert credits its full-parallel hybrid-drive system, which it says uses electric-motor power more efficiently than competing hybrid systems. The Fusion Hybrid tops out at 47 mph (76 km/h) on electric-only.

The Sonata Hybrid uses lithium-polymer batteries for storage, making Hyundai the first auto maker in the U.S. to retail a hybrid with a lithium battery. Hyundai makes a distinction between its lithium-polymer battery and lithium-ion batteries used in the upcoming, high-profile Chevy Volt and Nissan Leaf.

HEVs presently sold in the U.S. use nickel-metal-hydride-battery technology.

Hyundai says a higher energy density and the ability to handle more charge-discharge cycles are key advantages of lithium polymer batteries over Li-ions. Many small parts, causing a complex manufacturing process, and cell-to-cell inconsistency are other disadvantages of Li-ions.

The Sonata Hybrid’s 270V lithium-polymer battery is made by Korea’s LG Chem. After “hundreds of hours of testing” Hyundai promises a life of at least 10 years and 150,000 miles (241,402 km) for the battery.

The gasoline engine used in the Sonata Hybrid is a multi-port injected, Atkinson Cycle 2.4L 4-cyl., making 169 hp and 156 lb.-ft. (212 Nm) of torque. It is mated to a torque converter-less 6-speed automatic transmission and 30kW (40-hp) electric motor.

The torque converter is replaced by an electric motor and high-efficiency oil pump. Hyundai says the 6-speed automatic is preferred by consumers over continuously variable transmissions employed by other hybrids.

“One of the weak areas of the current Toyota (Motor Corp.) system that Ford (Motor Co.) and Nissan have licensed for their hybrids is that CVT system is always working against the generator,” Timothy White, senior manager-powertrain development, Hyundai-Kia America Technical Center Inc., told Ward’s recently

“On the highway, that’s not the most efficient way to operate. That’s why the highway number is always worse than the city number. Our system really overcomes that weakness by using the step-gear transmission.”

Total system output for the Sonata Hybrid is 209 hp, besting the Nissan Altima Hybrid, the current HEV leader, which churns out 198 hp.

Inside, the Sonata Hybrid uses a 4.2-in. (10.7-cm) liquid-crystal-display screen between the odometer and tachometer to monitor the hybrid system. Energy flow, driving mode, fuel level, battery-charge status and an Eco Level scoring system are shown. The latter has eight levels of sky color, gray to bright blue, to indicate the level of fuel-efficient driving.

The Sonata Turbo and Hybrid models go on sale in the U.S. later this year.

– with Tom Murphy

cschweinsberg@wardsauto.com