By Jim Kerr
Research and development is a big part of any automotive company. Bringing new technologies and products to market takes a lot of time and money. The introduction of even one new engine can take years to accomplish. That is why the sheer volume of new powertrain technology from General Motors this year is amazing. Hybrids, electric cars, diesels, direct fuel injection and more six-speed automatic transmissions are all in the near future. GM has many here now.
Hybrids attract a lot of attention. GM will have several on the road this year. Saturn Green Line hybrid models already include the Vue and now the Aura sedan. Chevy will join the group with the same Belt Alternator System (BAS) technology in the 2008 Malibu later this year. The BAS system uses a special Motor/Generator instead of a conventional alternator. A 42-volt battery pack provides power to the motor/generator unit to assist the gasoline engine during acceleration and the motor/generator unit recharges the battery during deceleration. This system also includes ‘autostop’, where the gasoline motor turns off at a stop sign and is started immediately again by the motor/generator when the brake pedal is released. This BAS system is a relatively low cost way of improving fuel economy and reducing emissions.
Later this year, look for the 2009 Saturn Vue two-mode hybrid, which like the new Chevy Tahoe and GMC Yukon hybrids, incorporates electric motors directly into the transmission. These vehicles can operate on electric motor propulsion only or a combination of gasoline and electric drive. Like the BAS system, regenerative braking from the motors is used to recharge the batteries, although the gasoline engine can also charge the batteries as well if necessary. The Vue system is expected to improve fuel economy about 45 percent over a non-hybrid, while the Tahoe and Yukon economy is estimated to have a 50% improvement during city driving cycles and a 30 percent improvement overall.
Companies such as Toyota, Mitsubishi and Nissan have already introduced vehicles with direct fuel injection. Now GM drivers can enjoy the improved fuel economy and power that direct fuel injection offers. The turbocharged Pontiac Solstice GXP and Saturn Sky Redline get a direct injected 2.0-litre four-cylinder engine, while the Cadillac STS and CTS are available with the direct injected 3.6-litre V6 engine. This 3.6-litre engine features four valves per cylinder, variable camshaft timing and fuel injectors that spray fuel directly into the combustion chamber instead of into the ports as on previous engines. This combines to produce 304 horsepower and a broad flat torque curve for spirited acceleration. Fuel consumption is reduced by three percent but another significant advantage of the fine fuel spray from the direct injectors is a dramatic 25 percent reduction in cold engine hydrocarbon emissions. Hydrocarbons are mainly unburned fuel so this engine is much more efficient as well as being powerful.
Performance enthusiasts are already talking about the 2008 Corvette’s new 6.2-litre LS3 engine. The 430 horsepower from this V8 engine, up 30 hp from last year, is the most powerful standard engine ever offered in a Corvette and it also makes the car the fastest automatic-equipped Corvette ever. What is really amazing about this powerplant is that even with the increase in horsepower, fuel economy remains the same as last year with an 8.1-litre per 100 km rating on the highway.
In other parts of the world, GM is launching five new 1.0-litre to 2.0-litre engines. They include gasoline and diesel engines. In Canada, the 6.6-litre Duramax diesel engine has received changes to reduce emissions and a revised 3.9-litre V6 gasoline engine is now offered in the Impala which combines variable valve timing, Active fuel management (cuts out cylinders during light load operation for up to 12% fuel economy savings) and E85 FlexFuel capability for the first time all in one package.
In addition to new engines, GM now has nine new six-speed automatic transmission models in production worldwide and is ready to introduce the tenth model in 2009. SUV’s, pickup trucks and passenger cars will all benefit from the four percent improvement in fuel economy and seven percent improvement in performance offered by the additional gear ratios.
Alternate fuels, hybrid vehicles and improvements to current gasoline engines are all in the GM portfolio for this year. Consumers are the big benefactors, as the bar for performance, driveability and economy is continually set higher. I look forward to the future.