2012 Buick LaCrosse eAssist Review | National Post Preview
2012 Buick LaCrosse e-Assist
By Gabriel Gelinas, National Post, Toronto
Palo Alto, Calif. – One will be hard-pressed to notice that Buick’s 2012 LaCrosse will soon be powered by a modified four-cylinder engine featuring a “light electrification” system. There are no markings anywhere on the car that indicate the presence under the hood of the latest evolution of GM’s mild hybrid system, which was initially developed for the Chevrolet Malibu hybrid. Dubbed e-Assist, this latest evolution pairs an electric motor supplied by a 115-volt lithium ion battery pack (good for a maximum output of 15 horsepower and 79 pound-feet of torque) with the 182-hp 2.4-litre four-cylinder Ecotec engine.
The liquid-cooled induction electric motor-generator is mounted at the front of the engine – where it replaces the conventional alternator – and is hooked up by way of a new engine belt drive. The battery pack and inverter module are located in a compartment between the rear seat and trunk, reducing cargo capacity to 10.8 cubic feet and blocking part of the pass-through opening between the trunk and the cabin.
As the primary objective of the e-Assist technology is to reduce fuel consumption, Buick engineers worked on reducing the weight of several components of the car to offset the added weight of the light electrification system, with the end result that the new model weighs only six kilograms more than a conventional LaCrosse. A number of aerodynamic tweaks were also added, such as the lower grille active shutter system borrowed from the Chevrolet Cruze Eco, which automatically closes at higher speeds – when cooling is least needed – redirecting airflow around the front and sides of the vehicle to reduce aerodynamic drag. Buick engineers have also added four underbody panels to streamline airflow underneath the car and fitted low-resistance tires supplied by Michelin to further improve efficiency. Buick claims the LaCrosse e-Assist will deliver fuel consumption figures of 5.4 litres per 100 kilometres on the highway and 8.3 L/100 km in the city. These figures seem optimistic given that I averaged 7.1 L/100 km on a test drive conducted mostly on highways and secondary roads, but that is still an impressive figure for a full-sized sedan.
Behind the wheel, there is practically no way to tell when the electric motor is active – unless one looks at the animated graphics on the centre display – because it operates seamlessly with the engine, providing an added boost only when needed. In terms of power, the LaCrosse e-Assist is not a rocketship, and you still have to consider passing manoeuvres with care despite the added torque delivered by the electric motor. However, an added and welcomed bonus of the e-Assist system is that the six-speed automatic transmission can hold a higher gear when climbing a grade, as the added power supplied by the electric motor eliminates the need for a downshift, making for a smoother drive. When coasting, fuel flow to the engine is cut and regenerative braking takes place as you come to a stop, with the engine now completely shut down. The engine refires only when you release the brake pedal and accelerate, which is one of a few subtle hints that you are not behind the wheel of a conventional automobile.
The ride is both smooth and very quiet but, while the LaCrosse is a competent performer, it is not a car that relishes being driven with enthusiasm. However, having spent some time in the Lincoln MKZ hybrid as well as the Lexus HS 250 hybrid, I can say that the Buick is quieter than the Lincoln and has a smoother ride than the Lexus.
The four-cylinder-powered 2012 LaCrosse will be the first model to use the new e-Assist technology, but plans are to extend it to other Buicks – such as the 2012 Regal – as well as other General Motors nameplates in the future. According to GM engineers, the e-Assist technology is easily scalable to different powertrains and platforms.
The Buick LaCrosse with e-Assist will arrive in Canadian dealerships by the end of summer, and will have a suggested retail price of $35,415, which is $1,015 more than the base V6-powered model.
Read article: http://www.nationalpost.com/cars/Preview+2012+Buick+LaCrosse+Assist/5064800/story.html