2005 Model Year Summary
· Application expanded
· Compact and lightweight modular design
· Eaton M62 supercharger and intercooled air induction manifold
· Robust head assembly
· Upgraded stainless steel intake valves
· Sodium filled exhaust valves
· Chain cam drive
· Robust piston and rod assembly
· Robust crankshaft
· Improved lubrication
· Fuel delivery
· Ignition system
· High flow exhaust
· Ecotec engine management system
FULL DESCRIPTIONS OF NEW AND UPDATED FEATURES
Introduced in 2004 on the Saturn ION Red Line, the Ecotec 2.0L SC (supercharged) also powers the 2005 Chevrolet Cobalt SS Supercharged coupe.
COMPACT AND LIGHTWEIGHT MODULAR DESIGN
GM Powertrain’s Ecotec 2.0-liter SC (supercharged) four-cylinder engine delivers impressive power for its size and weight. The Ecotec 2.0L SC slams out a formidable (estimated) 200 horsepower at 5600 rpm and a matching (estimated) 200 lb.-ft. of torque at 4400 rpm.
The ECOTEC engines are compact and lightweight. Even though the 2.0L SC includes a supercharger and intercooler, the fully-dressed powertrain requires no more space within an engine bay than the standard 2.2L unit. And at 330 pounds (150 Kg), the 2.0L SC weighs only 23 pounds (10 Kg) more than the 2.2L.
EATON M62 SUPERCHARGER AND INDUCTION SYSTEM
The Eaton M62 supercharger adds 40 percent more power to the Ecotec 2.0L engine compared to a naturally aspirated version. With its 12 psi maximum boost, the new generation Eaton M62 produces blower efficiency at lower rpm for improved durability and reduced noise while delivering instantaneous response with plenty of top-end power. The M62 supercharger utilizes a helical roots compressor and integral pressure control for optimal efficiency and durability. The boosted intake flow exits into an all-new matched intake manifold with an integral air-to-liquid heat exchange intake charge cooler system. An all-new compact single-track, six-rib belt supercharger drive system utilizes a linear tensioning device to further strengthen the already impressive system performance and durability. A microprocessor manages the M62 supercharger, fuel, direct spark delivery systems and the engine’s 68-mm electronic throttle control (ETC) system. ETC delivers outstanding throttle response, improved reliability and better integration with cruise control electronics for greater overall performance and driveability.
ROBUST HEAD ASSEMBLY
The head assembly on the Ecotec 2.0L SC engine is an advanced design. Semi-permanent mold technology produces a higher strength aluminum casting with enhanced port flow for improved induction and more efficient air delivery to the combustion chamber.
STAINLESS STEEL INTAKE VALVES
The Ecotec 2.0L SC engine design includes upgraded stainless steel intake valves for improved strength and corrosion resistance. Undercut stems are used to improve flow and reduce weight.
SODIUM-FILLED EXHAUST VALVES
The exhaust valves on the Ecotec 2.0L SC engine have sodium-filled stems that promote valve cooling, resulting in longer valve guide and seat life and more thorough combustion.
At normal engine operating temperatures, the sodium inside the valve stem fuses and becomes liquid. The liquid sodium improves conductivity, promoting heat transfer away from the valve face and valve guide to the cooler end of the stem where it can more readily dissipate. This helps maintain a lower and more uniform exhaust valve temperature while reducing wear on the valve guide for better alignment and a more positive seal between the valve seat and the valve face.
CHAIN CAM DRIVE
The camshafts on the Ecotec 2.0L SC engine are driven by a single roller chain that is only 12.5-mm wide compared to the much wider-toothed rubber-belt drive systems. The chain’s smaller dimensions contribute to shorter overall engine length for improved packaging efficiency.
ROBUST PISTON AND ROD ASSEMBLY
The Ecotec 2.0L SC engine is designed from the inside out to handle the demands of a 200-horsepower supercharged engine. A 5.6-mm piston top ring land is utilized for piston strength, allowing optimization of engine performance. The pistons themselves are cooled and lubricated by targeted oil jets that keep their underside, along with the cylinder wall, in a continuous oil bath. The large 23-mm piston pin provides a larger bearing surface to better handle the increased loads of a supercharged engine. The connecting rods have been upgraded, incorporating a larger forged I-beam section for added strength.
ROBUST DROP FORGED STEEL CRANKSHAFT
Like the upper end of the engine, the lower end of the Ecotec 2.0L SC engine is also built to provide lasting performance and durability. The crankshaft is a drop forged steel design that incorporates induction heat-treated fillets for added strength, and cross-drilled, chamfered oil passages for excellent lubrication characteristics.
With supercharged engines it is especially important to maintain a high level of lubrication that is effectively distributed to all moving parts. To that end, the Ecotec 2.0L SC engine is built with a large seven-quart oil sump and a crankshaft-driven pump. A block-mounted oil cooler is included to ensure proper lubricant cooling that promotes long engine life.
To better utilize the advantages of a supercharged engine, the Ecotec 2.0L SC engine is equipped with sequential port fuel injection and a 380 KPa /19.0 g/s returnless fuel delivery system that helps keep fuel cooler for more efficient combustion.
Performance objectives are also evident with the Ecotec 2.0L SC engine’s coil-on-plug ignition system that delivers maximum voltage to the spark plug for optimal firing and combustion characteristics. The system utilizes a 58X crankshaft position encoder system to ensure ignition timing will be accurate throughout the operating range of this performance engine.
HIGH FLOW EXHAUST
Completing the Ecotec 2.0L SC engine’s performance enhancements is a thin wall, large runner 2.25-inch exhaust manifold for improved flow and reduced back-pressure. High exhaust flow is achieved by utilization of a large 2.5 inch system, combined with a catalytic converter borrowed from the GM Truck line, and a much increased muffler volume. Low exhaust backpressure is a key contributer to the Ecotec 2.0L SC engine’s impressive performance.
ECOTEC ENGINE MANAGEMENT SYSTEM
The Ecotec's engine management system computer precisely controls the ignition and fuel injection system based on feedback from two oxygen sensors. The engine control Module (ECM) computer manages many additional system integrated functions such as on-board diagnostics, traction control calculations that adjust engine spark & the electronic throttle (ETC) to avoid wheel slip, and advanced cruise control logic. An added feature provided by the ECM is the monitoring of crankshaft movement, automatically cutting off power to the starter when the engine is already running.
The 2.0L SC engine is built exclusively at the FGP (Fiat-GM Powertrain) Kaiserslautern, Germany, engine-manufacturing facility. This plant uses a die-cast production technique that yields a block that is well suited for high-stress applications including turbocharging and supercharging. Variations of this block are also found in various Saab and Opel models. Compared to the original 2.2-liter Ecotec, the 2.0L SC features the same cylinder bore with a shorter stroke (94.6mm vs. 86.0mm). The shorter stroke helps the engine rev quickly and deliver lively throttle response.
Often referred to as the Global Four Cylinder, the starting point for the 2.0L SC is the Ecotec 2.2L (RPO L61). This engine has leveraged GM Powertrain’s worldwide design and engineering capability by drawing on the best practices of technical centers in North America and Europe. The Ecotec 2.2L created a template for subsequent global powertrain development that laid the groundwork for engines such as Powertrain’s new Global 3.6L V6. Most important, the Ecotec 2.2L is a world-class gasoline engine with obvious benefits for the customer. At 307 pounds fully dressed, the L61 is the lightest engine GM has produced in its displacement class, and one of the most compact four-cylinders in the world.
By 2003, all three Ecotec 2.2L assembly plants—Tonawanda, N.Y, Spring Hill, Tenn., and Kaiserlautern, Germany—were on line. The same year, in its continued commitment to environmental concerns and alternative fuels, GM Powertrain introduced an Ecotec 2.2L capable of operating on compressed natural gas (RPO L42). Available in the Chevrolet Cavalier through 2004, this bi-fuel engine ran on either gasoline or CNG, and switched seamlessly for one fuel to the other.
In any form, this inline four delivers excellent performance without sacrificing smooth, unobtrusive operation, and it was designed for minimal maintenance. The Ecotec 2.2L features an innovative paper oil-filter cartridge in a thin plastic frame for easy replacement and disposal. A hydraulic tensioner keeps the timing chain adjusted for life, and extended-life spark plugs deliver 100,000 miles of service. The Ecotec 2.2L gives GM a stronger presence in one of the industry's largest volume, most competitive displacement classes.
One of the Ecotec 2.2L engine program’s most significant contributions is in the manufacturing sector. The engine’s unique “lost-foam” aluminum casting method is environmentally benign: almost 100 percent of the sand used in the casting process can be recycled. The lost foam method also has another benefit: it allows thinner cross-section in many areas and cast-in features, which ease the job of machining the engine blocks and cylinder heads.
For the customer, the Ecotec 2.2L delivers performance, efficiency, low maintenance and smooth operation with technology familiar in premium V-type engines, including hydraulic roller finger valve operation and electronic “drive-by-wire”' throttle. For General Motors, this engine delivers manufacturing economies, maximum flexibility and broad application.
Although there are many versions of the Ecotec with distinct hardware differences and performance characteristics, all share the Ecotec family’s solid basic architecture and all-aluminum construction with:
· Dual overhead camshafts (DOHC) and four valves per cylinder
· Twin counter-rotating balance shafts to cancel the second-order shaking forces that cause noticeable vibration in four-cylinder inline engines
· Low-friction, roller-finger follower valvetrain with hydraulic lash adjusters
· Zero-maintenance chain camshaft drive
· Extremely compact dimensions and low mass
· Direct mounting of all ancillaries to the engine structure to eliminate common sources of noise, vibration and harshness
• Full circle transmission attachment is more rigid than most 4-cylinder powertrains for reduced noise and vibration
• GM Oil Life System for optimum oil change frequency
· No routine maintenance apart from oil/oil filter changes
· Catalyst located close to the exhaust manifold to speed catalyst “light-off” and reduce hydrocarbon emissions
Currently, the Ecotec is produced in three displacements (2.0L, 2.2L, 2.4L) and features four forms of induction; natural aspiration, natural aspiration with direct injection (gasoline), turbocharging, and supercharging.
Before going into production, every Ecotec engine variant is subjected to the toughest and most comprehensive validation process ever carried out at GM, having to pass all of the dynamometer and vehicle tests traditionally run by various GM organizations worldwide, including the most severe trials. Coinciding with the rollout of the Ecotec program, general engine durability testing on lab dynamometers was increased by 60 percent. This has been carried forward to the new Ecotec supercharged engine.
In another grueling validation test — the Thermal Cycle test — the supercharged engine was run up to maximum operating temperature, then flushed with ice-cold coolant, shocking the powerplant and its components into sudden contraction. This procedure was performed for 1,000 hours.
Validation included extensive real-world road testing in normal as well as extreme climates. Extensive testing was conducted at GM’s Desert Proving Ground in Arizona, and test trips through Death Valley, GM’s winter proving grounds at Kapuskasing in Ontario, Canada and altitude conditions across the Rocky mountains. The customer benefit from this arduous validation and testing is a powertrain product that offers extended life, high reliability and low operating costs.
The ultimate result is an engine that delivers impressive performance, yet is remarkably smooth and quiet with dependable operation, good fuel economy, great performance and low emissions.