2010 - LE8 Features and Benefits

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2010 Ecotec 2.2L I-4 VVT ( LE8 )
ECOTEC 2.2L I-4 (LE8) TRUCK ENGINE

2010 Model Year Features and Benefits Summary
Gen II Engine Block ( E85 Variant for Chevrolet HHR )
Cylinder Head Improvements
E37 Engine Control Module

Piston features
Oil Pump NVH improvement
Front Cover enhancement
Intake manifold
E85 Flex Fuel
Variable Valve Timing
Split Catalytic Converter

Full Description of Features and Benefits for 2010 model year.

E85 Flex Fuel engine for 2010 Chevrolet HHR
The Ecotec 2.2L I-4 VVT (LE8) powers the Chevrolet HHR Panel and Passenger Van for 2010 model year. This Ecotec engine is installed transversely, and equipped with either a Hydra-Matic 4T45 (MN5) FWD automatic or a Getrag F23/5 (M86) manual transmission. Horsepower improvements of up to seven horsepower gain will be realized in these applications and consistent with all new GM engine rpo’s, the (LE8) will be SAE Certified for 2010 model year.

Gen II Engine Block
The Ecotec 2.2L starts with a refined engine block, introduced for 2006 with the Ecotec 2.4L I-4 VVT (RPO LE5). The Gen II block was developed with data acquired in racing programs and the latest math-based tools. Both the bore walls and bulkheads, or the structural elements that support the crank bearings, have been strengthened, with only a minimal weight increase (approximately 2.5 pounds). The coolant jackets have been expanded, allowing more precise bore roundness and improving the block’s ability to dissipate heat. Coolant capacity increases approximately .5 liter.
The cylinder block is the engine’s foundation, and crucial to its durability, output and smooth operation. For GM, the common Gen II Ecotec block increases assembly efficiency. For the customer, the result is more efficient cooling, more strength to accommodate additional power, and better noise, vibration and harshness control.

Cylinder Head Improvements
The Ecotec 2.2L VVT I-4 also benefits from cylinder head refinements introduced on the 2.4L VVT. The exhaust ports have been enlarged slightly to expel exhaust gas more efficiently. The improvements to the cylinder head increase Ecotec 2.2L horsepower slightly in most applications (see specs). A semi –permanent mold (SPM), casting process with improved material properties was selected for these new heads. Upgraded valve seats on both the intake and exhaust ports improve durability and enable the engine to run on E85 fuel. The LE8 has High Silicon Molybdenum cast nodular iron exhaust manifold, chosen for its durability and sound-deadening properties.

E37 Engine Control Module
An advanced controller manages the multitude of operations that occur within the Ecotec 2.2L every split second. The E37 is the S-3 Controller within GM’s new family of three engine control modules (ECM) that will direct nearly all the engines in GM’s line-up. The E37 is the high-value variant, yet it’s anything but basic. It features 32-bit processing, compared to the conventional 16-bit processing in previous Ecotec 2.2Ls. It operates at 59 MHz, with 32 megabytes of flash memory, 128 kilobytes of RAM and a high-speed CAN bus, and it synchronizes several dozen functions, from spark timing to cruise control operation to traction control calculations. The E37 works roughly 50 times faster than the first computers used on internal combustion engines in the late 1970s, which managed five or six functions.

The family strategy behind GM’s new ECMs allows engineers to apply standard manufacturing, software and service procedures to all powertrains, and quickly upgrade certain engine technologies and calibration capabilities while leaving others alone. It creates both assembly and procurement efficiencies, as well as volume sourcing. In short, it creates a solid, flexible, efficient foundation, allowing engineers to focus on innovations and get them to market more quickly. The family of controllers means the ECM and corresponding connectors can be packaged and mounted identically in virtually every GM vehicle. GM creates all the software for the three ECMs, which share a common language and hardware interface that’s tailored to each vehicle.

The E37 also applies a new, rate-based monitoring protocol sometimes known as run-at-rate diagnostics. Rate-based diagnostics improve the robustness of the Onboard Diagnostics System (OBD II) and ensure optimal performance of emissions control systems. The new software increases the frequency at which the ECM checks various Ecotec 2.2L systems, and particularly emissions-control systems such as the catalytic converter and oxygen sensors. Rate-based diagnostics more reliably monitor real-world operation of these systems, and allow regulatory agencies to more easily measure and certify emissions compliance.

New Piston Features
The 2010 LE8 pistons have valve pockets to allow full use of the variable cam phaser and an anodized upper ring groove for improved durability. The oil control ring has lower tension for reduced friction and the upper compression ring is made of a new, more durable material, compatible with E85 fuel.

Front Cover Enhancements
For 2010, all Ecotec engine front covers incorporate a more efficient “Goosehead" port oil pump design, reducing cavitation at higher engine speeds and results in a measurable reduction in noise at the customer's ear, especially in cold-start and drive-away operation. The oil pump also includes a pressure-balanced oil relief valve, further improving the durability and reliability of the lubrication system, as well as a lower friction crank seal.

Intake manifold
The (LE8) intake manifold features a LE5 style welded seam composite manifold which contributes to engine mass reduction and NVH improvements while maintaining the
improved flow characteristics for improved engine performance numbers.

E85 Flexible-Fuel Capability (LE8)
GM has led the industry in introducing flex-fuel capability to its cars and trucks, and the new flex-fuel 2.2L I-4 VVT ( LE8 ) extends availability to an even broader range of customers. E85 is a clean-burning alternative fuel made in the United States from corn and other crops, composed of 85 percent ethanol alcohol and 15 percent gasoline. The 2.2L’s flex-fuel technology is both sophisticated and durable.

Flex fuel engines require special valves and valve seats to withstand the wear and corrosive effects of ethanol. The nitrided Silcrome 1 intake valves and 21-43 exhaust valves used in the 2.2L I-4 are up to the challenge. Compared to conventional iron-alloy valve material, nitrided Silcrome 1 includes tungsten, vanadium, manganese, silicone and higher chromium content. It is harder, and it improves durability, even under the rigors of ethanol operation. The 21-43 exhaust valves work equally well. Valve seat inserts have been upgraded to premium materials with a high percent of tool steel and solid lubricants resulting in excellent durability whether E85 or gasoline is run in the engine.

Hardware changes for flex-fuel operation are limited to the injectors. Because ethanol has fewer BTUs (less energy) than the same volume of gasoline, more fuel is required to produce the same horsepower at wide-open throttle. Flex fuel engines use unique stainless injectors with a greater cone angle and higher maximum fuel-flow rate. The fuel rail matches the injectors, but it’s manufactured of the same stainless steel used for all 2.2L I-4 fuel rails.

The flex-fuel 2.2L doesn’t require a special fuel sensor. The first flex-fuel engines used a light-reactive sensor to measure fuel composition from 100 percent gasoline to 85 percent ethanol. The 2.2L has a virtual sensor—software programmed in the E37 ECM with no separate physical sensor whatsoever. Based on readings from the oxygen (O2) sensors, fuel level sensor and vehicle speed sensors, the ECM adjusts the length of time the fuel injectors open for the type of fuel used. Within a few miles after filling up, the E37 controller determines what fuel is powering the 2.2L I-4 and manages the engine accordingly.

E85 fuel provides an environmentally friendly companion or alternative to gasoline. It is biodegradable and doesn’t contaminate the water supply. Ethanol can be produced from various feed stocks, including corn and wheat stalks, forestry and agricultural waste, and even municipal waste.

Variable Valve Timing
Variable Valve Timing (VVT) is included in these applications, and allows the powertrain system to take advantage of dual independent continuously variable valve timing for greater efficiency. Dual Independent VVT eliminates the compromise inherent in conventional fixed valve timing and allows a previously unattainable mix of low-rpm torque, even torque delivery over a broad range of engines speeds, and free-breathing high-rev horsepower.

The dual-independent cam phasers adjust intake and exhaust camshaft timing independent from one another for both intake and exhaust valves. A vane-type phaser is installed on the cam sprocket of both the intake and exhaust camshafts to turn these camshafts relative to the sprockets, thereby adjusting the timing of the valve operation. The vane phaser is actuated by hydraulic pressure from engine oil, and managed by a solenoid that controls oil pressure on the phaser. The phaser uses a wheel or rotor with five vanes (like a propeller) to turn the camshaft relative to the cam sprocket, which turns at a fixed rate via chain from the crankshaft. The solenoid directs oil to pressure ports on either side of the five phaser vanes; the vanes, and camshaft, turn as directed by this pressure. The more pressure, the more the phaser and camshaft turn. The engine control module directs the phaser to advance or retard cam timing, depending on driving demands. The dual-independent phasers can turn their respective camshafts over a range of 25 degrees relative to the cam sprocket, or 50 cam degrees from their parked positions.

The benefits are considerable. The cam phasers change valve timing on the fly, maximizing engine performance for given demands and conditions. At idle, for example, the intake cam is retarded and the exhaust cam is advanced which minimizes valve overlap, and allows for exceptionally smooth idling. Under other operating demands, the phasers adjust to deliver optimal valve timing for performance, drivability and fuel economy. At high rpm, the intake phaser might retard intake timing to maximize airflow through the engine and increase horsepower. At low rpm, the intake phaser advances to increase torque. Under a light load (say, casual everyday driving), the phasers are calibrated to select the optimum valve centerlines to maximize fuel economy. Without cam phasing, a cam design and valve timing must be biased toward one strength or another—high-end horsepower or low-end torque, for example—or profiled at some median level that maximizes neither.

The cam phaser is timed to hold the intake valve open a short time longer than a normal engine, allowing a reverse flow into the intake manifold. This reduces the effective compression ratio, allowing the expansion ratio to increase while retaining normal combustion pressures. Efficiency is gained because the high expansion ratio delivers a longer power stroke and reduces the heat wasted in the exhaust. This increase in efficiency comes at the expense of some power from the lower effective compression ratio, but that can be compensated for by the overall higher mechanical compression ratio.

Variable valve timing allows linear delivery of torque, with near-peak levels over a broad rpm range, and high specific output (horsepower per liter of displacement) without sacrificing overall engine response, or drivability. It also provides another effective tool for controlling exhaust emissions because it manages valve overlap at optimum levels.

Split Catalytic Converter (Improved Emissions Performance)
The Ecotec 2.2L I-4 VVT (LE8) engine mates up with a split converter architecture system in order to meet emission / diagnostic requirements. Ecotec engines meet BIN5 tailpipe emissions mandates in all applications. Bin 4 emissions levels in E85 equipped packages, To achieve this standard, the mix of precious metals in the catalytic converter has been reformulated. Metals such as platinum, palladium and rhodium in the converter’s catalytic substrate create the chemical reaction that turns the majority of exhaust emissions into harmless gases and water vapor.

Overview
Since the model year 2000 launch of the Ecotec 2.2L, the innovative strategy behind its versatile design has been validated by successful variants like the Ecotec 2.4L VVT (RPO LE5) and the ultra-high performance 2.0L direct-injection Turbo (RPO LNF). The 2.2L laid the foundation for a line of engines that share core components with minimal casting changes, yet deliver unique performance and market characteristics with a range of displacements, induction and fuel-delivery systems, and front and rear drive applications in both cars and trucks.

Introduced in 2000, the Ecotec 2.2L is often referred to as the Global Four Cylinder. It has leveraged GM’s worldwide design and engineering capability by drawing on the best practices of technical centers in North America and Europe. It also created a template for subsequent global powertrain development and laid the groundwork for engines such as GM’s global V-6 VVT.

At 305 pounds fully dressed, the 2.2L is the lightest engine GM has produced in its displacement class, and one of the most compact four-cylinders in the world. It features durability enhancements and technology familiar in premium V-type engines, including low-friction hydraulic roller finger valve operation and electronic “drive-by-wire” throttle in most applications. A hydraulic tensioner keeps the timing chain adjusted for life, and extended-life spark plugs deliver 100,000 miles of service. Routine maintenance is limited to oil and filter changes, and even those are made as easy as possible with a paper filter replacement cartridge and GM’s industry-leading Oil Life Monitoring System, which determines oil-change intervals according to real-world operation rather than a predetermined mileage interval.

Every engine in the Ecotec line has aluminum-intensive construction, with dual overhead camshafts (DOHC) and four valves per cylinder. Twin counter-rotating balance shafts cancel the second-order vibration inherent in four-cylinder inline engines, while direct mounting of accessories like the alternator and compressor eliminate common sources of noise, vibration and harshness. Full-circle transmission attachment and a structural oil pan improve powertrain rigidity.

The 2.2L has undergone the toughest and most comprehensive validation process in GM history, passing all of the dynamometer and vehicle tests traditionally run by various GM organizations worldwide. Validation included thousands of miles of real-world road testing in an extreme range of climates. Since the 2.2L’s introduction, virtually every system or component has been reviewed for improvement. Continual development has included optimized rod and main bearing material and shape changes, polymer coated pistons, and a new piston profile that reduces noise. Refinements such as an electrically operated power steering pump have been added to most Ecotec applications. The timing chain tensioner has also been redesigned for quieter operation

For all its design and production efficiencies and multitude of applications, the Ecotec 2.2L succeeds for one reason. It’s a world-class four cylinder engine that delivers excellent performance without sacrificing durability, economy or smooth, quiet operation.

The Ecotec engine variants are built at plants in Tonawanda, N.Y., Spring Hill, Tenn., and Kaiserslautern, Germany.