GM's Ecotec 2.2-Liter 4-Cylinder Engine Delivers
GM's Ecotec 2.2-Liter 4-Cylinder Engine Delivers Excellent Fuel Efficiency and Low Emissions in a Quiet, Reliable, Durable Package
Globally Designed Engine Powers 2002 Chevrolet Cavalier, Oldsmobile Alero, Pontiac Sunfire and Grand Am
, Saturn L-Series and VUE
- The Ecotec 2.2-liter engine, hailed as General Motors
' first truly global engine, delivers excellent fuel economy and low emissions in a reliable, durable package with low noise and vibration.
The lightweight aluminum four-valve overhead cam engine will be available in the 2002 Chevrolet Cavalier, Oldsmobile Alero, Pontiac Sunfire and Grand Am and Saturn L-Series and VUE. Chevrolet, Oldsmobile and Pontiac applications are rated at 140 horsepower with peak torque of 150 lb-ft. The Saturn VUE version is rated at 143 horsepower and 152 lb-ft of torque, with the L-Series rated at 135 horsepower and 142 lb-ft of torque.. The Ecotec 2.2-liter engine features a modular design, providing flexibility for a number of future technologies such as turbocharging, variable valve timing and direct injection-gasoline. Low maintenance is another key hallmark of this engine: oil and filter replacement is the only routine service required. The Ecotec 2.2-liter for North American applications are manufactured at one of the world’s largest engine plants in Tonawanda, New York. Other versions of the Ecotec 2.2-liter engine have already been introduced and well received in several other GM applications around the world. The engine debuted in the 2000 Saturn L-Series and is also featured in many 2001 European applications including the Opel Vectra, Astra, Zafira and Speedster.
Compact and Efficient: Lightweight Engine with Chain Drive
Both the cylinder head
and block of the engine are made of lightweight aluminum using the lost foam casting process (see below). Because of the utilization of modern design methods, the 2.2-liter unit weighs 139 kilograms (307 pounds, application dependent).The new engine family is also very compact in construction. The two overhead camshafts actuate the inlet and exhaust valves via roller finger follower rocker arms. This configuration results in a very compact cylinder head design. The camshafts are driven by a single roller chain only 12.5 millimeters wide as opposed to a much wider toothed rubber belt, resulting in shorter overall engine length for packaging and mass advantages. The Ecotec 2.2-liter has a stroke of 94.6 millimeters and a bore of 86 millimeters. Overall, in the new applications, the Ecotec 2.2-liter is only 665 millimeters long, 642 millimeters wide and just 655 millimeters tall (26.2 x 25.3 x 25.8 inches).
Low Vibration: Structural Oil Pan, Rigid Lower Crankcase, and Twin Balance Shafts
Smooth operation with very low noise and vibration is another important attribute of the Ecotec 2.2-liter engine. The counter rotating balance shafts are housed in the cylinder block to cancel the primary vertical imbalance inherent to 4-cylinder engines. The structural oil pan, box-like lower crankcase design, MLS (multi-layered steel) gasket and long cylinder head bolts (163 millimeters, 6.25 inches) provide a rigid structure for the engine. The 360 degree mounting flange for the transmission adds to the powertrain rigidity. All the accessories are directly mounted to the engine structure without any brackets, which helps eliminate noise and vibration.
Low Maintenance: Routine Maintenance Limited to Oil and Filter Change
Low maintenance is another customer advantage for the Ecotec 2.2-liter. In addition to a reduced space requirement, the timing chain with hydraulic tensioner requires no maintenance over its entire working life. The same applies to the high-performance ignition module, which is mounted directly in the cylinder head cover and has two individual ignition coils located directly above the platinum spark plugs. This arrangement eliminates spark plug wires, resulting in greater operating reliability and lower maintenance requirements. With hydraulic valve lash adjusters, the finger follower valvetrain also requires no routine maintenance. Overall, except for changing the engine oil and the fully recyclable oil filter, no routine maintenance is required.Use of roller finger followers provides about 5 percent reduction in friction compared to the conventional direct acting bucket-type cam followers. Fuel economy for the Grand Am and Sunfire with the automatic transmission are at 24 mpg city, 32 highway. The five-speed manual transmission versions are labeled at 25 city and 33 highway.
Emissions: Meeting Federal NLEV and California LEV Standards
To help meet emission standards, Ecotec's engine management system computer precisely controls the ignition and fuel injection based on feedback from the two oxygen sensors and handles on-board diagnostics.The exhaust outlet architecture, along with the control system, in most cases enables the Ecotec to meet or exceed the current emission standards, mainly without the use of Exhaust Gas Recirculation (EGR) or Air Injection (AIR). The rear facing exhaust results in a short distance to the catalytic converter for quick catalyst light off on cold starts. Other features like minimum gap platinum-tipped spark plugs and a 3-millimeter top ring land piston design also help to reduce the hydrocarbon (HC) emissions.
Lost Foam Casting: High Precision, Quality, Environmental Compatibility
The aluminum engine block and cylinder head are cast using GM's lost foam process. Pioneered by GM for large engine components, this is similar to the classic lost-wax process, which is used by jewelers and dentists for its high precision capability. Instead of the wax, a polystyrene pattern of the actual part is used. When the hot aluminum is poured into the mold it fills the space occupied by the polystyrene foam, which burns at high temperature and evaporates as a gas. This gas can then be easily treated to make harmless before releasing into the atmosphere.The lost foam process is noted for its environmental friendliness in contrast to the sand core process. With lost foam, 100 percent of the sand is recycled. The process also enables the casting of thinner cross sections for the cylinder walls and smaller passages to eliminate machining operations.
World Engine Family: GM Powertrain, Opel and other GM Organizations Join Forces
The Ecotec 2.2-liter is a member of GM’s global 4-cylinder engine family developed by an international team which included engineers from Opel's International Technical Development Center in Rüsselsheim, Germany; GM Powertrain in Pontiac, Michigan; and Saab in Trollhäten, Sweden. This engine family has flexibility to cover a 1.8 to 2.2-liter displacement range and will power a wide variety of GM vehicles worldwide."Cooperation with our colleagues in the global GM alliance gave us access to many synergy effects for the new engine generation which will be installed in numerous cars worldwide," said Walter Schnittger, chief project engineer at Opel. "To satisfy the requirements of the relevant markets and car platforms effectively, we made the basic engine as versatile as possible."More than 230 engineers and technicians joined forces to develop the Ecotec engine family. For the first time within GM, 100 percent of the engine components were modeled in 3-dimension using GM's state-of-the art computer aided design software."This resulted in significant advantages by reducing the number of math models conventionally needed," said Jay Subhedar, assistant chief engineer at GM Powertrain.The individual component math models could be used to create experimental and production tools and could be electronically assembled to represent the engine assembly for virtual packaging studies. Within hours, it was possible to transmit electronic models of components or complete engines from one development center to another via satellite, shortening the work process by days or even weeks.
Built to Last: Most Demanding Validation Process in GM’s History
Before going into production, the new engine family was subjected to the toughest and most comprehensive validation process ever carried out at GM."Being a global engine, the Ecotec 2.2-liter had to pass all the dynamometer and vehicle tests traditionally run by the various GM organizations worldwide," said Subhedar.After careful comparison, the team included the most severe tests in the validation test matrix. For example, the number of hours for the General Engine Durability test on lab dynamometers was increased by 60 percent. In another grueling experiment, the Thermal Cycle test, the engine is run to achieve maximum operating temperature and then flushed with ice-cold coolant, shocking the components into sudden contraction. This procedure was carried out for 1,000 hours.The test program also included extensive real-world road testing in normal as well as extreme climates. Besides extensive testing at GM’s Desert Proving Ground in Arizona and test trips through Death Valley, the engine was also tested in the sand and dusty environment of the Australian Outback. Cold-weather validation was conducted near the Arctic Circle in Sweden and at GM’s winter proving grounds at Kapuskasing in Ontario, Canada. As a result of this arduous testing, customers benefit from extended engine life, high reliability, and low operating costs.