ANN ARBOR, MI – While top executives continue to stress the need to develop electric vehicles, General Motors, Toyota and Fiat Chrysler Automobiles also are pushing ahead with strategies to improve the performance and efficiency of internal-combustion engines – both gasoline and diesel.
“The internal-combustion engine will be around for a long time,” says Bruce Belzowski, managing director of Automotive Futures at the University of Michigan and organizer of the “Powertrains for the 21st Century” conference here.
At the same time, automakers are facing tough new regulations on efficiency and emissions, he says. “It’s a global demand.”
Norman Peralta, GM’s director of global propulsion, says even as the company works toward its goal of zero emissions, gasoline likely is to remain the dominant fuel through 2050, according to estimates from the U.S. Energy Information Admin.
Thus, GM is looking at a full range of technologies to improve the efficiency of its future propulsion systems such as downsized turbocharged engines, new valvetrain designs, dynamic fuel management, thermal management and multispeed transmissions as well as new designs for CVTs and diesel engines.
The new 2.7L 4-cyl. that will be used in the ’19 Silverado includes a valvetrain that enhances cylinder deactivation. The valve lifts higher at full power and lower at cruising speed and fuel efficiency improves 24% when the engine is operating on two cylinders, Peralta says.
Dynamic Fuel Management, with 17 different firing fractions or patterns, is used on the V-8 in the ’19 Silverado, he says. Active thermal management helps the engine warm up faster with an integrated rotary valve and a new electric water pump on the new truck.
Peralta says GM also has spent close to $1 billion on a new 1.6L diesel engine and is preparing to introduce a new 3.0L Duramax V-6 diesel that will be available on light-duty trucks.
“From a General Motors viewpoint, diesel is one of the most efficient powertrains,” Peralta says. “Diesel is an important part of our portfolio, but it might not make sense from a regulatory standpoint. Diesels might work best in U.S. pickup trucks. Might not work in some regions.”
GM expects to have 20 new electrical-vehicle architectures by 2023, Peralta says, noting electrification is a game changer when the battery also becomes a structural element. In addition, GM’s work on electric vehicles has given the company the industry’s deepest battery expertise and a competitive advantage at a critical time.
“We are extremely proud of the Bolt EV,” he says.
Mike Dahl, FCA’s head of engine programs and propulsion planning, says electric propulsion will blend with conventional IC powertrains as the technology is refined. For example, electric motors can replace the existing mechanically driven axles and could shift between full electric drive and augmenting the IC engine. An electric motor could be linked to an IC engine’s crankshaft.
The development of future IC engines and powertrains also will require manufacturers to take advantage of other technologies such as lightweight materials throughout the vehicle, aerodynamic improvements and low rolling-resistance tires. It also will encompass downsized turbocharged engines and 8- and 9-speed transmissions.
Dahl suggests the key to the acceptance of new powertrains, both conventional and electric, is that performance-wise it must be “invisible” to the consumer. “It really needs to be transparent from a usage standpoint,” he says.
At the same time, the addition of new technology also must add to the consumer’s value equation. Owners of the Jeep Wrangler prize the vehicle’s low-end torque, and an electrified powertrain can be designed to boost the low-end torque of the Wrangler, pleasing the customer, Dahl says. FCA also is looking at the heavy electrification of trucks in the future.
Regulations also will play a major role in shaping FCA’s powertrain portfolio, Dahl says.
In Brazil, for example, ethanol made from sugar cane is widely used for fuel in internal-combustion engines, but there also is interest in electric vehicles in the country’s sprawling cities, he notes. In Europe, electrification likely will replace small-displacement diesel engines, and in the U.S. long commutes make plug-in hybrids desirable even as consumers shift to trucks and SUVs.
While Toyota is very proud of the work it has done with hybrids, “we look at technology agnostically,” says Ben Schlimme, Toyota Motor North America powertrain executive manager. “We look at it as a way to pull in the customer. You’ve got to key in on the program demands.”
Different regions have different demands. Toyota has an extensive program to develop the sources of hydrogen required for fuel cells in Japan. But it also is preparing battery-electric vehicles for markets in China and will continue to work on more efficient internal-combustion engines for deployment in North America where gasoline is expected to be the fuel of choice for the foreseeable future.
The improvements in IC engines produced under the Toyota New Global Architecture (TNGA) already have produced impressive results on vehicles such as the new Camry, boosting fuel economy 25% while improving engine output 15%. At the same time, carbon-dioxide emissions have dropped 15%.
The broad plan for the TNGA architecture includes a 3.5L Dynamic Force twin-turbo V-6, Dynamic Force 2.0L and 2.5L engines and a 10-speed automatic transmission. Toyota also expects to introduce a solid-state battery for use in hybrids and battery-electric vehicles in 2020.
By 2025, Toyota expects 5.5 million, or about half of all the cars it builds annually, to be electrified as part of the company’s quest for better fuel economy and reduced emissions, Schlimme says.
Toyota has some 4,500 employees devoted to the development of electrified vehicles, ranging from mild hybrids to full hybrids and battery-electric vehicles. The Japanese automaker plans to have an electrified version of every vehicle in its lineup by the middle of the next decade.
