2014 C7 Corvette
Chevrolet unveiled the all-new Gen V small block V8 engine that will power the 2014 C7 Corvette. The new V8 will be designated the LT1 – the third time Chevrolet has used this RPO for a Corvette engine. Estimated power will be 450 horsepower and 450 lb-ft of torque and with a variety of fuel saving technologies, the new Corvette is estimated to get 26+ MPG.
• New Chevrolet Corvette V8 is 6.2 liters, designated LT1. This is the 3rd time for a Corvette engine to use that RPO code.
• 0 to 60 mph in less than 4 seconds. Entry-level car. 450 hp or more!
• New Corvette will use cylinder deactivation. Will go from 6.2 V8 to 3.1 V4 for better fuel economy.
• New V8 engine has 11.5:1 compression ratio. Direct fuel injection, cylinder deactivation; continuously variable valve timing; active fuel management
• 450 hp 450 lb-ft of torque. More than 26 mpg!
• New engine has a unique and complex piston head.
• New LT1 V8 has 50 lb-ft more low-end torque than current LS3 V8; matches the LS7 V8 from the Z06.
• LT1 engine to be built at Tonawanda engine plant in Buffalo, NY
• Premium fuel recommended, but not required.
• Spark plug is in the center of the chamber. Intake and exhaust valves are reversed.
• There will be an optional 11.5 quart dry sump oil system available for the new LT1 V8
• 6,600 RPM fuel cut off in the new LT1 motor
• All the new technologies on the LT1 make it a heavier motor than the LS3
• Patent-pending PCV system
• Final performance ratings will come in 2013
• Peak horsepower around 6,000 RPM; peak torque around 4,000 RPM
• New combustion process to be documented in an SAE paper to be published in the Spring of 2013
• LT1 is the first OHV engine with Direct Injection
“The Holy Grail for developing a performance car is delivering greater performance and more power with greater fuel economy and that’s what we’ve achieved,” said Tadge Juechter, Corvette chief engineer. “By leveraging technology, we are able to get more out of every drop of gasoline and because of that we expect the new Corvette will be the most fuel-efficient 450 horsepower car on the market.”
The LT1 is the first of the all-new 5th generation of small blocks and is packed full of technology. The quantity of carryover parts is so small that they’ll fit into a sandwich bag. Everything else is new. Here are a few of the highlights:
• The most powerful standard Corvette ever, with preliminary output of 450 horsepower (335 kW) and 450 lb.-ft. of torque (610 Nm)
• The quickest standard Corvette ever, with estimated 0-60 performance of less than four seconds
• The most fuel-efficient Corvette ever, exceeding the 2013 EPA-estimated 26 miles per gallon on the highway.
• Advanced combustion system optimized with 6 million hours of analysis
• Direct injection
• Active Fuel Management (AFM)
• Continuously variable valve timing
• 40 pounds lighter than BMW’s twin-turbo 4.4L, DOHC V-8 with similar output.
• All-aluminum block and oil pan
• Advanced oiling system, with available dry-sump system:
• Four-into-one exhaust manifolds
New Corvette will use cylinder deactivation. Will go from 6.2 V8 to 3.1 V4 for better fuel economy. No, no, no. I still remember the troubled with V8-6-4 concept in the '80s. Porsche has even a worst idea, shutting down the engine while coasting or at a stop (I think you can override this). I don't want this nonsense idea in my sports car.
It's still a pushrod engine. :( My 3.6 liter twin turbo engine produces 480 hp, 502 lb-ft at 1950 rpm
Advanced combustion system optimized with 6 million hours of analysis
"The Corvette LT1 represents the most significant redesign in the Small Block's nearly 60-year history – building on its legacy to make one of the world's best engines even better," said Sam Winegarden, vice president, Global Powertrain Engineering. "More than just great horsepower, the LT1 has been optimized to produce a broader power band. Below 4,000 rpm, the torque of the Corvette LT1 is comparable to that of the legendary, 7.0L LS7 out of the current Corvette Z06. The LT1 is a sweetheart of a power plant and drivers will feel its tremendous torque and power at every notch on the tachometer."
Increased power and efficiency were made possible by an unprecedented level of analysis, including computational fluid dynamics, to optimize the combustion system, the direct injection fuel system, active fuel management and variable valve timing systems that support it. More than 10 million hours of computational analysis were conducted on the engine program, including 6 million hours (CPU time) dedicated to the advanced combustion system.
Direct injection is all-new to the engine architecture and is a primary contributor to its greater combustion efficiency by ensuring a more complete burn of the fuel in the air-fuel mixture. This is achieved by precisely controlling the mixture motion and fuel injection spray pattern. Direct injection also keeps the combustion chamber cooler, which allows for a higher compression ratio. Emissions are also reduced, particularly cold-start hydrocarbon emissions, which are cut by about 25 percent.
Active Fuel Management (AFM) – a first-ever application on Corvette – helps save fuel by imperceptibly shutting down half of the engine's cylinders in light-load driving.
Continuously variable valve timing, which GM pioneered for overhead-valve engines, is refined to support the LT1 AFM and direct injection systems to further optimize performance, efficiency and emissions.
These technologies support the all-new, advanced combustion system, which incorporates a new cylinder-head design and a new, sculpted piston design that is an integral contributor to the high-compression, mixture motion parameters enabled by direct injection.
The LT1 head features smaller combustion chambers designed to complement the volume of the unique topography of the pistons' heads. The smaller chamber size and sculpted pistons produce an 11.5:1 compression ratio, while the head features large, straight and rectangular intake ports with a slight twist to enhance mixture motion. This is complemented by a reversal of the intake and exhaust valve positions, as compared to the previous engine design. Also, the spark plug angle and depth have been revised to protrude farther into the chamber, placing the electrode closer to the center of the combustion to support optimal combustion.
The pistons feature unique sculpted topography that was optimized via extensive analysis to precisely direct the fuel spray for a more complete combustion. The contours of the piston heads are machined to ensure dimensional accuracy – essential for precise control of mixture motion and the compression ratio.
I'm convinced that the LT1 is a good engine. How can it not be with all the buzz words? Do you think only the LT1 engine gets that type of analyses and tests? I would think all engine engineers do that for all high performance engines. This is still one of my favorite test :thumbup:
Race-proven legacy, state-of-the-art performance
The first Small Block V-8 debuted in the Corvette in 1955. It displaced 4.3L (265 cubic inches) and was rated at 195 horsepower, drawing air and fuel through a four-barrel carburetor. Five years later, V-8 power helped Corvette secure its first victory at the 24 Hours of Le Mans.
In 2012, the Small Block-powered Corvette Racing C6.R beat Ferrari, BMW and Porsche to sweep the drivers’, team, and manufacturer championships in production-based American Le Mans Series GT class. These championships make Corvette Racing the most successful team in ALMS history, with a total of 77 class wins, eight drivers’ championships, and nine manufacturer and team championships since 2001.
“The engine requirements for a production car and a race car are remarkably similar,” said Jordan Lee, Small Block chief engineer and program manager. “In both cases, you want an engine that is powerful and efficient, compact and lightweight, and durable. That combination is what made the original Small Block so successful. Today, the introduction of state-of-the-art technologies and engineering makes one of the best performance car engines in the world even better.”
As an example, the new LT1 engine is 40 pounds lighter than a competitor’s twin-turbo 4.4L, DOHC V-8 with similar output. That weight savings not only improves the Corvette’s power-to-weight ratio, but also contributes to a near-perfect 50/50 weight balance for enhanced steering response and handling.
The new LT1 is also four inches shorter in overall height than the competitive DOHC V-8. That also improves handling by lowering the center of gravity while enabling a low hood line – contributing to the Corvette’s iconic profile, as well as ensuring exceptional driver visibility.
“The power and efficiency of the Small Block V-8 are hallmarks of Corvette performance,” said Lee. “But, the compact size and great power-to-weight are just as important for the overall driving experience. The all-new LT1 will play a huge role in making the all-new Corvette a world-class sports car, in terms of technology, performance, and refinement.”
Corvette Racing 2012 ALMS Season Summary
GT Manufacturer Champion: Chevrolet
GT Team Champion: Corvette
GT Driver Champions: Oliver Gavin, Tommy Milner
Michelin Green X Challenge GT Manufacturer Champion: Chevrolet
Michelin Green X Challenge GT Team Champion: No. 3 Corvette C6.R, Jan Magnussen/ Antonio Garcia
All-aluminum block and oil pan
The Gen 5 block was developed with math-based tools and data acquired in GM’s racing programs, providing a light, rigid foundation for an impressively smooth engine. Its deep-skirt design helps maximize strength and minimize vibration. As with the Gen 3 and Gen 4 Small Blocks, the bulkheads accommodate six-bolt, cross-bolted main-bearing caps that limit crank flex and stiffen the engine’s structure. A structural aluminum oil pan further stiffens the powertrain.
The block features nodular iron main bearing caps, which represent a significant upgrade over more conventional powdered metal bearing caps. They are stronger and can better absorb vibrations and other harmonics to help produce smoother, quieter performance.
Compared to the Gen 4 engine, the Gen 5’s cylinder block casting is all-new, but based on the same basic architecture. It was refined and modified to accommodate the mounting of the engine-driven direct injection high-pressure fuel pump. It also incorporates new engine mount attachments, new knock sensor locations, improved sealing and oil-spray piston cooling.
Advanced oiling system, with available dry-sump system:
The LT1 oiling system – including oil-spray piston cooling – was also optimized for improved performance. It is driven by a new, variable-displacement oil pump that enables more efficient oil delivery, per the engine’s operating conditions. Its dual-pressure control enables operation at a very efficient oil pressure at lower rpm coordinated with AFM and delivers higher pressure at higher engine speeds to provide a more robust lube system for aggressive engine operation.
Standard oil-spray piston cooling sprays the underside of each piston and the surrounding cylinder wall with an extra layer of cooling oil, via small jets located at the bottom of the cylinders. For optimal efficiency, the oil jets are used only when they are needed the most: at start-up, giving the cylinders extra lubrication that reduces noise, and at higher engine speeds, when the engine load demands, for extra cooling and greater durability.
An available dry-sump oiling system promotes exceptional lubrication system performance during aggressive driving maneuvers and high cornering loads. It includes two stages: a pressure stage and a scavenge stage. The pressure stage includes the new, dual-pressure-control and variable-displacement vane pump.
Dexos semi-synthetic motor oil, with a 5W30 specification, helps reduce friction to further enhance the LT1’s efficiency.
New, tri-lobe camshaft
Compared to the Gen 4 Small Block, the camshaft remains in the same position relative to the crankshaft and is used with a new rear cam bearing, but it features an all-new "tri-lobe" designed lobe which exclusively drives the engine-mounted direct injection high-pressure fuel pump, which powers the direct-injection combustion system. The cam's specifications include 14mm/13.3mm (0.551/0.524-inch) intake/exhaust lift, 200/207-crank angle degrees intake/exhaust duration at 0.050-inch tappet lift and a 116.5-degree cam angle lobe separation.
New, cam-driven fuel pump: The direct injection system features a very-high-pressure fuel pump, which delivers up to 15Mpa (150 bar). The high-pressure, engine-driven fuel pump is fed by a conventional fuel-tank-mounted pump. The direct injection pump is mounted in the "valley" between cylinder heads – beneath the intake manifold – and is driven by the camshaft at the rear of the engine. This location ensures any noise generated by the pump is muffled by the intake manifold and other insulation in the valley.
bunch of misfit engineering jargon. all those numbers, so what, are they good? :rofl:
I remembered all those "sophisticated" wording in my design review presentations at NASA that nobody cared to understand. :rofl:
PCV-integrated rocker covers
One of the most distinctive features of the new engine is its domed rocker covers, which house the, patent-pending, integrated positive crankcase ventilation (PCV) system that enhances oil economy and oil life, while reducing oil consumption and contributing to low emissions. The rocker covers also hold the direct-mount ignition coils for the coil-near-plug ignition system. Between the individual coil packs, the domed sections of the covers contain baffles that separate oil and air from the crankcase gases – about three times the oil/air separation capability of previous engines.
Intake manifold and throttle body assembly: The LT1's intake manifold features a "runners in a box" design, wherein individual runners inside the manifold feed a plenum box that allows for excellent, high-efficiency airflow packaged beneath the car's low hood line.
Acoustic foam is sandwiched between the outside top of the intake manifold and an additional acoustic shell to reduce radiated engine noise, as well as fuel pump noise.
The manifold is paired with an electronically controlled throttle, featuring an 87mm bore diameter and a "contactless" throttle position sensor design that is more durable and enables greater control.
Four-into-one exhaust manifolds
The LT-1 uses a cast version of the "four-into-one" short-header exhaust manifold design used on the Gen 4 LS7 engine. The cast header passages enable consistent exhaust flow into the "wide mouth" collector at the converter.
sexy car. not looking forward to seeing my car depreciate :lol:
wonder if chevy is finally going affix proper seats to the corvette.
I hope the rear does not look like their Camaro. Need a shark fin to make the roof line look hot. :)
The only thing missing from the rear of that car is a Transformer's badge.
I really dislike the current GM sharp line designs; Camaro, Corvette, Cadillac. Buick seems much more relaxed about having to make a big "look at me" statement. :eek:
Cooling system, humidity sensor and more: Additional features and technologies of the Gen 5 Small Block include:
A revised cooling system with an offset water pump and thermostat for more efficient performance
Air induction humidity sensor ensures optimal combustion efficiency, regardless of the surrounding air's humidity
58X ignition system with individual ignition coil modules and iridium-tip spark plugs
All-new E92 engine controller.
General Motors' investment in the Gen 5 Small Block will create or retain more than 1,600 jobs in five North American plants, including Tonawanda, New York, which recently received upgrades to support its production.
OOOOOOHHHHH, an offset water pump. :rolleyes:
Moderators, I know this poster has been around a long time, but he's basically a bot that just cuts and pastes stories and links straight from manufacturer's sites (without proper links and use of quoting blocks) and never engages in any conversions.
How does this help "bring the community together"? It may be not be a direct violation of the TOU, but its sure against the spirit.
A friend of mine purchased a brand new Cadillac with that infamous 8-6-4 engine. Before the end of the first year ownership, he was ready to take out his shotgun and shoot the engine
in front of the dealership in Dallas. They took back that lemon in a fairly favorable trade-in.
I just got a 2013 328i and there is only one thing we hate, the implementation of ASS.
Luckily, it's got an Off position. Still, whenever one of us forget to shut ASS off, it's unnerving as all hell when you are in thick city traffic. Dealer promised us to take care of it. Next time we go shopping at the BX in Ft Worth, we'll drop it off and drive a loaner for a couple of hours.
I think this new C7 Vette should be quite nice. With 26-28 MPG it should be much better than my current M3. Let's see how the interior turns out to be. My guess is that it should not be too bad.
Computational analysis on the Gen 5 Small Block that debuts in the next Chevrolet Corvette began five years ago and has consumed 0.1 quadrillion bytes of disk space on General Motors’ computers. That’s the equivalent of 18 billion typed pages or 23,000 DVD discs.
Much of the analysis was devoted to the engine’s all-new advanced combustion system, which supports a trio of Next-Gen technologies never before used together on the Corvette, including direct injection, Active Fuel Management and variable valve timing. They contribute to preliminary output of 450 horsepower (335 kW), making the new 6.2L LT1 the most powerful and efficient standard engine ever offered in the Corvette.
Thirty analysts worked on the Gen 5 on their computers – including the development of all-new software – for several years before the first physical test engine was built, creating a design that is more volumetrically efficient than the Gen 4 Small Block. In addition to the advanced combustion system, they designed and evaluated every component in the engine, from the connecting rods to the rocker covers. They used a variety of commercially available software and proprietary software developed by General Motors.
Designers had to start from scratch when it came to the design of the Gen 5’s new combustion system. The overhead valve arrangement and two-valves-per-cylinder arrangement was completely different than the DOHC design of GM’s other direct-injected engines. The flow field – the motion of the air/fuel mixture – is more complex with an overhead-valve design and direct injection requires more mixture swirling for optimal combustion.
To deliver on the horsepower, torque and efficiency goals for the engine, they had to determine:
• The optimal placement of the injector in relationship to the spark plug within the combustion chamber
• The optimal size of the intake and exhaust valves – and the angles at which they’d be held in the cylinder head
• The size and volume of the combustion chamber
• The configuration of the piston head, which is crucial in supporting direct injection combustion.
More than 75 iterations of combustion systems for the Gen 5 were developed and evaluated through computational analysis, before a final design was selected. The resulting cylinder head configuration for the Gen 5 is all-new, along with a new, dished piston design. They work cohesively to exploit the high-compression, mixture motion parameters enabled by direct injection. Smaller combustion chambers complement the dish volume of the pistons’ heads. The pistons also feature “risers” at the top to direct the fuel spray for a more complete combustion.
Another significant change is the reversal of the position of the intake and exhaust valves, compared to the Gen 4 Small Block. The change, which is supported by an all-new intake manifold design, enabled a straighter path for the air charge into the combustion chamber. The airflow enters the combustion chambers via large, 2.13-inch (54mm) hollow intake valves and exits through 1.59-inch (40.4mm) hollow sodium exhaust valves. The valves are held at new, 12.5-degree intake/12-degree exhaust angles, vs. the Gen 4’s 15-degree angle, and they are splayed slightly to reduce shrouding and enable greater airflow.
Additional analysis-driven engine design features include:
• Knock performance was improved over the Gen 4 design, which enabled a higher compression ratio that supports greater power
• The spark plug was also moved closer to the center of the combustion chamber, pushing the flame for the combustion process closer to the center of the cylinder – an essential enabler of the direct injection system’s efficiency
• The configuration of the exhaust port supports a minute amount of exhaust gases to be drawn back into the cylinder during the next combustion cycle, for a more complete burn that enhances efficiency and reduces emissions
• Displacement of the Corvette’s LT1 engine was optimized at 6.2L for sustaining fuel-saving cylinder deactivation with Active Fuel Management, based on the car’s weight and the engine’s torque output
• Dozens of iterations of the wet- and available dry-sump oiling systems for the Corvette were evaluated to ensure optimal performance during the high loads of driving on a racetrack.
Computational analysis also drove mass optimization and noise-reducing initiatives with the Gen 5 Small Block, all of which supporting the implementation of the new combustion system. The direct injection system, for example, uses an engine-mounted, camshaft-driven high-pressure fuel pump. Because the feature had never been implemented on a Small Block, analysis drove the design of components such as the intake manifold, oil pan and more. The computer tests calculated the resonance of the components to predict their noise levels and “played” them against one another to determine probably noise and vibration sources. Component designs, including shape and sized, were refined until noise and vibration targets were achieved.
Inside the engine, the shapes and configurations of the rotating parts were evaluated for mass optimization, ensuring the highest quality and durability was achieved with the lightest, most efficient parts. When the need for a change was identified, it could often be implemented within a week, rather than several weeks or even months, when compared to evaluating physical components.
There is a YouTube video showing the biggest Achilles heel of Corvette being fixed.
Also here is the leaked Road & Track cover showing the real deal....
Looks like the viper but in digging it!
BigMarcus ~ EVO 4G LTE
~ Big Marcus
The Official Manhattan unveiling of the C7 Corvette is Wednesday, Jan 16th. I have an invitation and am planning on attending.
The new Gen 5 Small Block’s lubrication system supports Next-Gen advanced technologies, including Corvette’s first applications of direct injection, Active Fuel Management and continuously variable valve timing. They help the completely reengineered 6.2L engine produce the greatest standard horsepower, torque and efficiency in the car’s 60-year history.
• Standard wet-sump lubrication or available high-performance dry-sump system
• All-new variable-displacement, dual-pressure-control oil pump with increased flow capacity for optimal oiling efficiency
• Pressure-activated oil-spray piston cooling for greater efficiency, durability and quietness
• New windage tray design enhances oil flow control and crankcase breathing
• Rocker covers with patent-pending positive crankcase ventilation system for greater oil life and lower oil consumption
• Dexos semi-synthetic motor oil, including a 5W30 specification for the Corvette, that helps reduce friction to enhance the engine’s efficiency.
The available dry-sump oiling system promotes exceptional lubrication system performance during extended high-rpm use under high cornering loads. It includes two stages of oil pumping, including the new, dual-pressure-control and variable-displacement vane pump and a scavenge pump.
Variable displacement enables the Gen 5’s oil pump to efficiently deliver oil as demanded by the engine’s operating conditions. Its dual-pressure control enables operation at a very efficient oil pressure at lower rpm coordinated with the Active Fuel Management and operation at a higher pressure at higher engine speeds providing a more robust lube system with aggressive engine operation. As with Gen 3 and Gen 4 Small Block engines, the new vane-type oil pump is crankshaft-driven.
Oil-spray piston cooling, in which eight oil-spraying jets in the engine block drench the underside of each piston and the surrounding cylinder wall with an extra layer of cooling, friction-reducing oil, is standard on all Gen 5 engines – previously it was only a feature of the supercharged LS9 and LSA engines. The oil spray reduces piston temperature, promoting extreme output and long term durability. The extra layer of oil on the cylinder walls and wrist pins also dampens noise, for a quieter driving experience.
For optimal efficiency, the oil jets are used only when they’re needed the most: At start-up, giving the cylinders extra lubrication that enhances the engine’s durability, and at higher engine speeds, when the engine load demands it.
A redesigned windage tray is also used with the Gen 5, featuring a new oil scraper design. It enhances performance and efficiency by improving oil flow control and bay-to-bay crankcase breathing. The tray is mounted on the bottom of the engine, between the main bearing caps and oil pan.
Dry sump details
The dry sump system scavenges liquid oil and any resulting mixture of oil, air and crankcase gases from the bottom of the engine oil pan through an internal scavenge return tube. This oil mixture is pumped to the top of the dry sump tank (mounted in the engine compartment but external to the engine). Within the tank, the oil mixture is tangentially spilled out on a spiral-shaped internal baffle where the contact and flow about the internal surfaces of the tank promote separation of air and gasses that are entrained in the oil. These gasses are directed by the PCV system (see section below) through a series of baffles and tubes back to the combustion chamber to be burned.
The de-aerated oil is directed down the walls of the tank to collect in the 10.5-quart reservoir (wet-sump application feature a six-quart capacity), conditioned and ready for use. The second stage of the dual-stage gerotor pump then draws the conditioned oil from the tank and pressurizes it, feeding it to the engine via the oil filter and oil cooler. The routing of the engine oil to and from the dry sump reservoir also provides the benefit of passive oil cooling.
PCV-integrated rocker covers
One of the most distinctive features of the all-new Gen 5 engine is its domed rocker covers, which house a patent-pending integrated positive crankcase ventilation (PCV) system that enhances oil economy and oil life, while reducing oil consumption. It also contributes to low emissions for the Gen 5.
The rocker covers also hold the direct-mount ignition coils for the coil-near-plug ignition system. Between the individual coil packs, the domed sections of the covers contain baffles that separate oil and air from the crankcase gases – about three times the oil/air separation capability of previous engines. Each cover features and inlet and outlet path for the crankcase gases, with the separated oil dropping back onto the engine within the covers and the remaining air/gases circulated back into air intake stream for combustion. The system also prevents moisture from accumulating in the engine.
This integrated PCV system is an essential contributor of the Gen 5’s efficient performance and long-term durability – and the domes for it on the rocker covers make the Gen 5 engine instantly recognizable.
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