GM - Modifiche 2007-2010 ai motori ECOTEC II e V6 H.F.

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2007 Ecotec 2.2L I4

ECOTEC 2.2L I4 CAR AND TRUCK ENGINE

2007 Model Year Summary

Gen II Engine Block

Cylinder Head Improvements

New Camshaft Design

E37 Engine Control Module

58X Crankshaft Reluctor Ring

Digital Crank and Cam Sensors

Individual Coil-on-Plug Ignition

Vented Starter Solenoid

New MAP Sensor

New Intake Manifold Seals

New Oil Filter Element

Improved Emissions Performance

Full Description of New and Updated Features

Gen II Engine Block

The Ecotec 2.2L starts with a refined engine block, introduced for 2006 with the Ecotec 2.4L 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, as in the new Ecotec 2.0L direct-injection Turbo (RPO LNF) and better noise, vibration and harshness control.

Cylinder Head Improvements

The Ecotec 2.2L also benefits from cylinder head refinements introduced on the 2.4L VVT. The exhaust ports have been enlarged slightly with machining improvements to expel exhaust gas more efficiently. Both engines share a common nodular cast iron exhaust manifold, chosen for its durability and sound-deadening properties. The improvements to the cylinder head increase Ecotec 2.2L horsepower slightly in most applications (see specs).

New Camshaft Design

The exhaust cam has been re-profiled to take advantage of refinements in the cylinder head. Maximum exhaust valve lift does not change, but duration increases slightly. The cams also feature a new 4X timing reluctor, replacing timing sensors previously contained in the ignition-coil cassette (see Individual Coil-On-Plug ignition, below). The powder metal reluctor wheel is pressed onto the camshaft at the rear. The 4X reluctor improves ignition timing accuracy and maintains precise consistency over the life of the engine.

Individual Coil-On-Plug Ignition

The Ecotec 2.2.L is equipped with individual coil-on-plug ignition, or four separate coils. Each coil sits directly over a spark plug, with no wire in between. Previous Ecotec 2.2Ls had two coils in a single cassette, with each coil shared by two spark plugs. Individual coil-on-plug delivers maximum voltage and the most consistent spark density. The 2.2L’s cast aluminum cam cover has been redesigned to accommodate the four coils.

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 Powertrain’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. Powertrain 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.

58X Crankshaft Reluctor Ring

The Ecotec 2.2L has an advanced 58X crankshaft position encoder to ensure that ignition timing is accurate throughout its operating range. The 58X ignition system uses a unique crankshaft ring and sensor to provide the new E37 ECM more immediate information on the crankshaft’s position during rotation. This allows the controller to adjust ignition timing with greater precision, which optimizes performance and economy. Engine starting also is more consistent with reduced crank time. The powder metal 58X reluctor ring is bolted to a crankshaft counterweight.

Digital Crank and Cam Sensors

New digital sensors are common with the Ecotec 2.4L VVT and, with the 4X intake cam and 58X crank reluctors along with the new E37 ECM, they complete the ignition timing loop. This dual-position sensing system ensures extremely accurate timing for the life of the engine.

Vented Starter Solenoid

A new starter solenoid helps ensure starting performance in extreme cold temperatures. The solenoid case now has a micromesh-covered vent and an O-ring between the case and the starter motor. The mesh protects the solenoid from debris particles but prevents moisture buildup in the case. When the Ecotec 2.2L is warm, any moisture on the solenoid evaporates through the vent. The vented solenoid virtually eliminates the possibility of cold-start problems associated with solenoid icing.

New MAP Sensor

An advanced manifold absolute pressure (MAP) sensor completes upgrades to the Ecotec 2.2L’s control system. The MAP sensor is a variable resistor used to monitor the difference between atmospheric and manifold pressure, which tends to increase when the engine is operating under a higher load or at wide-open throttle. The ECM uses information from the MAP sensor to adjust spark timing and fuel delivery to optimize performance and minimize emissions. The new MAP sensor improves fidelity, or accuracy, and takes full advantage of the E37 ECM’s capabilities.

New Intake Manifold Seals

The Ecotec 2.2L is equipped with new intake manifold and throttle body sealing gaskets manufactured from a fluorocarbon material. The new gaskets are more resistant to most chemicals, for maximum durability, and particularly impermeable to hydrocarbon molecules. Gasoline vapor cannot penetrate the new seals, virtually eliminating evaporative emissions.

New Oil Filter Element

The paper element in the Ecotec 2.2L oil filter has been improved. The engine’s innovative filter design uses a replaceable cartridge without the conventional metal filter can, which traps waste oil that can not easily be removed. The cartridge can also be changed from under the hood, without getting under the car, and it virtually eliminates spillage during replacement. The new element filters particles from the oil more effectively without disrupting oil flow.

Improved Emissions Performance

The Ecotec 2,2L now meets BIN5 tailpipe emissions mandates in all applications. 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. With the new intake sealing gaskets, the 2.2L also meets PZEV (Partial Zero Emission Vehicle) Enhanced Evaporation standards.

Overview

The upgrades for 2007 point out an ongoing theme for the Ecotec 2.2L I4: continuous improvement to a ground-breaking engine from a company with a long history of other ground-breaking engines and transmissions.

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-, 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 Powertrain’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 Powertrain’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.

http://media.gm.com/us/powertrain/en/product_services/2007/Whats%20New/07_L61.doc

più interessante il v6 3.6 litri in cui si parla di un iniezione indiretta bosch a doppio getto in previsione dell'imminente pari cilindrata a iniezione diretta multigetto di cui ho parlato in messaggio nel vecchio forum:

2007 GM 3.6L V6 VVT (LY7)

3.6L V6 VVT (LY7) CAR AND TRUCK ENGINE

2007 Model Year Summary

Higher Output Application in 2007 Saturn Outlook

New Application in 2007 Pontiac G6 and Saturn Aura

Smaller Pitch Timing Chain

Dual-Spray Fuel Injectors

Improved Oil Pan

Full Description of New and Updated Features

Higher Output Application for 2007 Saturn Outlook

A new high-output version of the 3.6L V6 VVT powers the new Saturn Outlook crossover sport-utility vehicle. This engine is a transverse installation, matched with GM Powertrain’s new 6T75 Hydra-Matic six-speed automatic transmission and either front- or all-wheel drive.

The 3.6L V6 VVT HO generates more horsepower thanks to changes in the cylinder heads and induction system, increasing airflow through the engine. The intake ports have been reshaped to increase flow, and a new intake manifold features longer runners that reduce airflow restrictions. Finally, the exhaust cams have been re-profiled to speed the flow of exhaust gas out of the engine at wide-open throttle. Maximum lift does not change, but duration increases to keep the exhaust valves open a fraction longer. Preliminary figures indicate a horsepower increase of nearly six percent compared to the previous most powerful version of the 3.6L V6 VVT.

The higher output version retains the 3.6L V6 VVT’s sophisticated variable intake system. The aluminum intake manifold has a valve in its plenum, managed by the engine control module (ECM), which opens and closes according to engine speed. At idle, the valve is open. From just past idle to mid rpm, the valve closes and effectively creates two separate plenums, each feeding the intake runners and ports for half of the cylinders. This optimizes airflow at lower engine speeds to maximize low-end torque. At higher engine speeds, the plenum plate opens, creating a single, higher-volume plenum feeding all cylinders for freer breathing and high-rev horsepower. The variable intake manifold (VIM) allows optimal airflow for a given engine speed without the compromises of a fixed-volume plenum. In combination with cam phasing, it means impressively linear torque delivery.

This higher output version of the 3.6L V6 VVT features its own comprehensive acoustic package, with a full sound-dampening cover between the cam covers. The base Outlook will be equipped with single exhaust in both front- and all-wheel drive variants. All other vehicles built with the higher-output 3.6L V6 VVT will feature dual exhaust.

New Application in 2007 Pontiac G6 and Saturn Aura

The 3.6L V6 VVT is available as an option on the G6 coupe and sedan and the all-new Aura sedan. This is a transverse installation. Accessory drive is similar to that in the Buick LaCrosse, but in the G6 and Aura the 3.6L V6 VVT will be equipped with Powertrain’s new 6T70 Hydra-Matic six-speed automatic transmission.

Smaller Pitch Timing Chain

The 3.6L V6 VVT in the Cadillac CTS has a new timing chain with a smaller pitch (7.7 mm compared to 9.5mm previously) and more links. The chain features an inverted tooth design. The smaller links engage at a lower impact speed, which decreases the noise generated. In conjunction with the new chain, the number of teeth on the sprockets is also increased, increasing the meshing frequency and further reducing noise and vibration.

The new timing chain is a running change that will occur in all of GM Powertain’s V6 VVT engines through the course of the 2007 model year.

Dual-Spray Fuel Injectors

Fuel injectors on the 3.6L V6 VVT now have two tiny spray nozzles. Developed with Bosch, the dual-spray injectors improve fuel atomization in the combustion chambers compared to single-tip injectors, allowing more complete combustion. The new injectors allow better emissions management. All 3.6L V6 VVTs except those built for the Buick LaCrosse are equipped with the dual-spray fuel injectors.

Improved Oil Pan

The oil pan on 3.6L V6 VVTs built for the Cadillac CTS, SRX and STS have been stiffened to improve powertrain rigidity and reduce vehicle vibration. The oil pan bolts to the transmission bell housing as well as the engine block, eliminating points of vibration.

Overview

Introduced in the 2004 Cadillac CTS and SRX, the 3.6L V6 VVT (RPO LYZ) was the first in GM Powertrain’s global family of high-feature V6 engines. Its architecture was jointly developed by GM technical centers in Australia, Germany, the United States and Sweden. The 3.6L VVT V6 is based on the philosophy that a true family of global engines provides the best value and performance for the customer and the best return on investment for General Motors. It applies the most advanced automotive engine technology available, from state-of-the-art casting processes to full four-cam phasing to ultra-fast data processing and torque-based engine management. Since its launch, application has spread to an expanding number of vehicles for one primary reason. The 3.6L V6 VVT delivers a market-leading balance of good specific output, high torque over a broad rpm band, fuel economy, low emissions and first-rate noise, vibration and harshness control, with exclusive durability enhancing features and very low maintenance.

The 3.6L V6 VVT’s engine block is cast with sand molds from A319 aluminum, with strong cast-in iron bore liners, six-bolt main bearing journals and inter-bay breather vents. Cylinder heads are also aluminum. Four valves per cylinder and a silent chain valvetrain contribute to both smoothness and high output. Four-cam phasing changes the timing of valve operation as operating conditions such as rpm and engine load vary. That means smooth, even torque delivery with high specific output (horsepower per liter of displacement) and excellent specific fuel consumption. Cam phasing also pays big dividends in reducing exhaust emissions. By closing the exhaust valves late at appropriate times, the cam phasers create an internal exhaust-gas recirculation system. The 3.8L V6 VVT meets all emissions mandates without complex, weight-increasing emissions control systems such as EGR and air injection reaction (AIR).

Aluminum-intensive construction extends to the pistons, which are manufactured of forged aluminum and considerably lighter than conventional steel pistons. Less weight means less reciprocating mass in the engine, which in turn means less inertia and greater operating efficiency. Moreover, the V6 VVT pistons are crafted with a number of features that enhance durability and reduce noise and harshness, including a high-tech polymer coating and floating wrist pins. The V6 VVT engine family was developed with pressure-actuated oil squirters in all applications. Three jet assemblies in the block hold a pair of oil-squirting nozzles that drench the underside of each piston and the surrounding cylinder wall with an extra layer of cooling, friction-reducing oil. The jets reduce piston temperature, which in turn allows the engine to produce more power without reducing long-term durability. The extra layer of oil on the cylinder walls and wristpin further dampens noise emanating from the pistons.

The oil pan provides another example of extensive efforts to minimize noise and vibration in the 3.6L V6 VVT. Cast aluminum dampens internal engine noise better than a conventional stamped steel pan. Structurally, it is considerably stiffer. The design was optimized with math-based analysis and carefully crafted curves in the pan’s sides and bottom. These reduce the broadcasting or “drumming’’ of noise created as oil flows through the crankcase, and they increase bending stiffness in the pan.

The 3.6L V6 VVT is managed the Bosch Motronic ME9 controller. This sophisticated electronic control module (ECM) uses a torque-based control strategy, which improves upon throttle-based management systems that rely exclusively on a throttle position sensor to manage electronic throttle control. The torque-based strategy measures the position of the intake plenum plate, cam phasing positions and other operational parameters and translates that data into an ideal throttle position and engine output, based on the driver’s positioning of the gas pedal. The ECM and a wide range of sensors allow failsafe systems, including ignition operation in the event of timing sensor failures. The control software protects the V6 VVT from permanent damage in the event of complete coolant loss, and allows the engine to operate at reduced power for a prescribed distance sufficient for the driver to find service. It also allows a number of other customer-friendly features, including GM's industry-leading Oil Life System, which determines oil change intervals by actual operation parameters, rather than a preset mileage limit.

The cam drive and valvetrain components require no scheduled maintenance. A sophisticated cam-chain tensioner, high-quality cam phasing components and hydraulic lash adjusters are designed to ensure optimal valvetrain performance for the life of the engine with no adjustment. Even perishable components provide extended useful life. The spark plugs have dual-platinum electrodes and a service life of 100,000 miles without degradation in spark density. The plugs are easy to remove because they are located in the center of the cam cover. Extended life coolant retains its cooling and corrosion-inhibiting properties for 100,000 miles in normal use. The two accessory-drive belts were specified primarily for low-noise operation, yet they are manufactured of EPDM rather than neoprene and should last the same 100,000 miles before replacement is recommended. The oil filter requires only element replacement, and it’s designed to virtually eliminate spillage when the cartridge is removed.

The V-6 VVT development and production teams made assembly efficiency a priority. All global V6 variants can be built with no significant casting changes to major components. Core engine components are designed to be common whenever possible. The basic V6 block is used in all vehicle applications, with differences limited to machining. While different vehicles require different oil pans, the pan’s mating surfaces with the engine block and transmission are common in all cases, allowing considerable assembly efficiencies. The net result is streamlined procurement practices, fewer tool changes in the plant, shorter assembly time and improved quality for the customer.

Production for the 3.6L V6 VVT is located in St. Catharines, Ontario, Canada and Port Melbourne, Australia.

http://media.gm.com/us/powertrain/en/product_services/2007/Whats%20New/07_LY7_%20APP042606.doc

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nel vecchio forum le prime notizie, ora è arrivato

[simonepietro]

New base engine in Cadillac STS, optional in CTS

Advanced multi-outlet fuel injectors for direct combustion chamber fuel injection

High-pressure engine-driven fuel pump for multiple injection events

Variable pressure, stainless steel fuel rail

Advanced engine control module (ECM) for direct injection control

All applications matched to 6L50 six-speed automatic transmission

New direct injection engine keeps oil life monitoring system

Variable intake dropped

Cam phasing coupled with direct injection further reduces exhaust emissions

Cast aluminum cylinder block and heads

Double overhead cams with four valves per cylinder

Cams driven by small-pitch, quiet chain

Variable valve timing with four-cam phasing for precise intake and exhaust tuning

High-power and high efficiency 11.3:1 compression ratio

Lightweight strong forged aluminum pistons with low-friction wrist pins

Oil jets cool the pistons, while polymer-coated skirts reduce noise and friction

Durable forged crankshaft, and precision sinter-forged connecting rods

Cast aluminum structural oil pan and steel baffles stiffens block and reduces noise

Electronic throttle control with advanced integrated cruise control

Reliable coil-on-spark-plug ignition

Optimally tuned exhaust manifolds with close-coupled catalytic converters

Composite camshaft covers are fully isolated and reduce noise

Numerous other noise, vibration and harshness controls

Exclusive durability enhancements and minimal maintenance requirements

Manufacturing techniques refined for exceptional quality and line efficiency

Full Description of New and Updated Features

New base engine in Cadillac STS, optional in CTS

The 3.6L VVT V6 DI engine will for the first time debut in the Cadillac STS as the base engine, and in the CTS as an optional engine. The induction system for the CTS has been completely redesigned, and that results in slightly greater output (see specifications).

Advanced multi-outlet fuel injectors for direct combustion chamber fuel injection

Conventional port-injected engines inject fuel upstream of the intake valve into the intake port, and this fuel and air mixture enters the combustion chamber when the intake valve opens. On the direct-injection 3.6-liter VVT DI, fuel is injected directly into the combustion chamber during the intake stroke, at which time only air flows through the intake system and into the combustion chamber when the intake valve opens.

During the subsequent compression stroke, the fuel and air mixture now in the combustion chamber is ignited conventionally by the spark plug.

The special injectors that inject fuel directly into the combustion chamber are located beneath the intake ports, which transfer only air. Because the ports are not used to mix the fuel and air, efficiency of the air flow is increased. In addition, the accuracy in which the fuel can be injected through special direct injectors is greater, and the end result is better fuel consumption at all throttle openings, and better mixture control which allows higher compression. The higher compression ratio also increases combustion efficiency over a conventionally injected engine. The special direct injectors have been developed to withstand the greater heat and pressure inside the combustion chamber, and also utilize multiple outlets for best injection control.

The increased combustion efficiency helps to reduce emissions, particularly during cold starts, which is when the bulk of emissions are created. In the example of the new 3.6L VVT DI, the compression ratio is increased to 11.3:1, aiding power output and fuel efficiency.

The 3.6-liter VVT DI is based on GM Powertrain’s sophisticated 60-degree dual overhead cam (DOHC) V6 engine. It is the latest member of a growing family of GM Powertrain V6 engines developed for applications around the world, drawing on the best practices and creative expertise of GM technical centers in Australia, Germany, North America, and Sweden.

High-pressure engine-driven fuel pump for multiple injection events

To overcome the higher pressures inside the combustion chamber, as well as supply the multiple injection points of the direct injection nozzles, an engine-driven high-pressure pump supplies fuel to the injectors. This high-pressure pump feeds a high-strength fuel rail that feeds a continuously variable pressure fuel rail attached to the injectors. The high-pressure pump is supplied by a conventional fuel pump mounted in the fuel tank. The high-pressure pump can supply up to 1,740 psi (120 bar) of pressure, although it is dependent upon fuel demand by the engine. For example, at idle, the fuel system is regulated to about 508 psi (35 bar) and increases with demand. The high-pressure pump is mounted on the end of the cylinder head and is driven by the exhaust cam.

Advanced electronic control module (ECM) for direct injection control

To control the precise amount of fuel injected into the combustion chamber and the pressure of the fuel, and the exact timing for the injection events, a new engine controller is necessary for the 3.6 V6 VVT DI.

All applications matched to 6L50 six-speed automatic transmission

The 3.6 VVT V6 DI engine will be mated to the 6L50 six-speed automatic transmission

New direct injection engine keeps oil life monitoring system

It also allows a number of other customer-friendly features, including GM's industry-leading Oil Life System, which determines oil change intervals by actual operation parameters, rather than a preset mileage limit.

Cam phasing coupled with direct injection further reduces exhaust emissions

Cam phasing pays big dividends in reducing exhaust emissions by optimizing exhaust valve overlap and eliminating the need for a separate exhaust gas recirculation (EGR) system.

Overview

Introduced in the 2004 Cadillac CTS and SRX, the 3.6L V6 VVT (RPO LYZ) was the first in GM Powertrain’s global family of high-feature V6 engines, with four cam, four valves per cylinder configuration, with the cams driven by maintenance free silent primary chain drive. Its architecture was jointly developed by GM technical centers in Australia, Germany, the United States and Sweden. The 3.6L VVT DI V6 is based on the philosophy that a true family of global engines provides the best value and performance for the customer and the best return on investment for General Motors. It applies the most advanced automotive engine technology available, from state-of-the-art casting processes to full four-cam phasing to ultra-fast data processing and torque-based engine management. Since its launch, application has spread to an expanding number of vehicles for one primary reason. The 3.6L V6 VVT delivers a market-leading balance of good specific output, high torque over a broad rpm band, fuel economy, low emissions and first-rate noise, vibration and harshness control, with exclusive durability enhancing features and very low maintenance.

Like earlier versions of the high-feature V6, the 3.6-liter VVT DI employs four cam phasing to change the timing of valve operation as operating conditions such as rpm and engine load vary. The result is linear delivery of torque, with near-peak levels over a broad rpm range, and high specific output (maximum horsepower per liter of displacement) without sacrificing overall engine response and drivability. When combined, direct-injection and cam phasing technologies enable an unmatched combination of power, efficiency and low-emissions in gasoline V6 engines.

By closing the exhaust valves late at appropriate times, the cam phasers allow the engine to draw the desired amount of exhaust gas back into the combustion chamber, reducing unburned hydrocarbon emissions. The return of exhaust gases also decreases peak temperatures which contributes to the reduction of oxides of nitrogen (NOx) emissions. In tandem with the dramatic 25-percent reduction in cold-start hydrocarbon emissions brought on by direct-injection, the 3.6-liter VVT DI V6 surpasses all emissions mandates, and does so without complex, weight-increasing emissions control systems such as EGR and air injection reaction (AIR).

The 3.6L V6 VVT DI has a new timing chain with a smaller pitch (7.7 mm compared to 9.5mm previously) and more links. The chain features an inverted tooth design. The smaller links engage at a lower impact speed, which decreases the noise generated. In conjunction with the new chain, the number of teeth on the sprockets is also increased, increasing the meshing frequency and further reducing noise and vibration.

The new timing chain is a running change that will occur in all of GM Powertain’s V6 VVT engines through the course of the 2007 model year.

The oil pan on 3.6L V6 VVT DI is stiffened to improve powertrain rigidity and reduce vehicle vibration. The oil pan bolts to the transmission bell housing as well as the engine block, eliminating points of vibration. The oil pan provides another example of extensive efforts to minimize noise and vibration in the 3.6L V6 VVT. Cast aluminum dampens internal engine noise better than a conventional stamped steel pan. Structurally, it is considerably stiffer. The design was optimized with math-based analysis and carefully crafted curves in the pan’s sides and bottom. These reduce the broadcasting or “drumming’’ of noise created as oil flows through the crankcase, and they increase bending stiffness in the pan.

Like the conventionally injected 3.6L V6 VVT, the direct injection engine’s block is cast with sand molds from A319 aluminum, with strong cast-in iron bore liners, six-bolt main bearing journals and inter-bay breather vents. Cylinder heads are also aluminum. Four valves per cylinder and a silent chain valvetrain contribute to both smoothness and high output. Four-cam phasing changes the timing of valve operation as operating conditions such as rpm and engine load vary. That means smooth, even torque delivery with high specific output (horsepower per liter of displacement) and excellent specific fuel consumption. Cam phasing also pays big dividends in reducing exhaust emissions. By closing the exhaust valves late at appropriate times, the cam phasers create an internal exhaust-gas recirculation system. The 3.8L V6 VVT meets all emissions mandates without complex, weight-increasing emissions control systems such as EGR and air injection reaction (AIR).

Aluminum-intensive construction extends to the pistons, which are manufactured of forged aluminum and considerably lighter than conventional steel pistons. Less weight means less reciprocating mass in the engine, which in turn means less inertia and greater operating efficiency. Moreover, the V6 VVT pistons are crafted with a number of features that enhance durability and reduce noise and harshness, including a high-tech polymer coating and floating wrist pins. The V6 VVT engine family was developed with pressure-actuated oil squirters in all applications. Three jet assemblies in the block hold a pair of oil-squirting nozzles that drench the underside of each piston and the surrounding cylinder wall with an extra layer of cooling, friction-reducing oil. The jets reduce piston temperature, which in turn allows the engine to produce more power without reducing long-term durability. The extra layer of oil on the cylinder walls and wristpin further dampens noise emanating from the pistons.

The crankshaft is a strong forged steel, and connecting rods are sinter forged, as are other 3.6L V6 VVT engines. The camshaft covers are fully isolated composite material covers that also perform as a noise barrier.

The 3.6L V6 VVT is managed the Bosch Motronic MED9 controller. This sophisticated electronic control module (ECM) uses a torque-based control strategy, which improves upon throttle-based management systems that rely exclusively on a throttle position sensor to manage electronic throttle control. Cruise control is also integrated into the electronic throttle control. The torque-based strategy measures the cam phasing positions and other operational parameters and translates that data into an ideal throttle position and engine output, based on the driver’s positioning of the accelerator pedal. The ECM and a wide range of sensors allow failsafe systems, including ignition operation in the event of timing sensor failures. The ignition is individual coil-on-plug. The control software protects the V6 VVT from permanent damage in the event of complete coolant loss, and allows the engine to operate at reduced power for a prescribed distance sufficient for the driver to find service. It also allows a number of other customer-friendly features, including GM's industry-leading Oil Life System, which determines oil change intervals by actual operation parameters, rather than a preset mileage limit.

Low Maintenance

The cam drive and valvetrain components require no scheduled maintenance. A sophisticated cam-chain tensioner, high-quality cam phasing components and hydraulic lash adjusters are designed to ensure optimal valvetrain performance for the life of the engine with no adjustment. Even perishable components provide extended useful life. The spark plugs have dual-platinum electrodes and a service life of 100,000 miles without degradation in spark density. The plugs are easy to remove because they are located in the center of the cam cover. Extended life coolant retains its cooling and corrosion-inhibiting properties for 100,000 miles in normal use. The two accessory-drive belts were specified primarily for low-noise operation, yet they are manufactured of EPDM rather than neoprene and should last the same 100,000 miles before replacement is recommended. The oil filter requires only element replacement, and it’s designed to virtually eliminate spillage when the cartridge is removed.

The 3.6L direct injection V6 VVT variant can be built with no significant casting changes to major components than the conventionally injected 3.6L VVT V6 built in St. Catharines, Ontario and Melbourne, Australia. Core engine components are designed to be common whenever possible. The basic V6 block is used in all vehicle applications, with differences limited to machining. While different vehicles require different oil pans, the pan’s mating surfaces with the engine block and transmission are common in all cases, allowing considerable assembly efficiencies. The net result is streamlined procurement practices, fewer tool changes in the plant, shorter assembly time and improved quality for the customer.

Production of the 3.6L V6 VVT DI is located in Flint, Michigan.

www.GM.com

[Touareg 2.5]

... Motori e aggiornamenti riguardanti i motori postiamoli in tecnica.. vale lo stesso per il boxer subaru

[simonepietro]

per me va bene. Si tratta di una vecchia discussione.

[simonepietro]

forse un ulteriore versione del v6 3.6 che conferma direttamente e indirettamente alcune notizie di AX riguardanti pure un marchio nostrano

GDI Powers CTS to New Heights

By Tom Murphy

WardsAuto.com, Oct 1, 2007 10:35 AM In addition to supplying gasoline direct injection for the production V-6, Bosch produces a concept CTS with a twin-turbo GDI V-6 that stacks up nicely against the V-8 in the ’05

[simonepietro]

Arrivati i variatori/e di fase pure sul 2.2 ecotec, in versione Fuel-flex

The HHR will be available with an Ecotec 2.2-liter or Ecotec 2.4-liter four-cylinder engine, both of which will be compatible with E85. For the first time, the Ecotec 2.2L is equipped with variable valve timing (VVT), technology that assures precise opening and closing of the valves and accurate control of combustion gases to improve engine performance and efficiency. The Ecotec 2.4L continues to offer VVT.

[Betha23]

Hai fatto un thread dove hai scritto e ti sei risposto da soloooooooooooo!!!!!!!!!!!!!!!!!!!!!!

[simonepietro]

uso autopareri come archivio personale così salvaguardo la memoria del mio P.C.

Sarà un uso improprio di autopareri?

[stev66]

No...assolutamente.

Si tratta di notizie comunque interessanti per tutti.