2014 Corvette/C7

[ubengineering]

@08GT500

I love everything about this vette except the hideous rear end. Wtf over.

Hideous!? That’s the best part of the whole car! I almost like it as much as the Ford GT! I’ll meet you half way on the exhaust though. If I were to buy one of these I would get an aftermarket dual exhaust and lose two of the pipes.

[misteroman]

I’m sure there will be a new Z in the stable to along side the 427 and GS when they allow the gm dicount. That is just one great car.

[articzap]

…

@Big Boss"

I guess I’ll let this be a C7 thread exclusive, more on the C7.R

(Press Release)

• Co-developed with 2015 Corvette Z06, sharing chassis, engine technologies and aerodynamics strategy
• Makes competition debut Jan. 25 at the 52nd Rolex 24 At Daytona
• Continues legacy of Corvette Racing, which includes 90 global victories and 10 manufacturer championships since 1999

DETROIT – Chevrolet today unveiled the Corvette C7.R race car, which was co-developed with the all-new 2015 Corvette Z06. They represent the closest link in modern times between Corvettes built for racing and the road, sharing unprecedented levels of engineering and components including chassis architecture, engine technologies and aerodynamic strategies.

“When it comes to endurance racing, Corvette has been the benchmark of success for nearly 15 years,” said Jim Campbell, U.S. vice president, Performance Vehicles and Motorsports. “A great deal of the team’s success can be attributed to the symbiotic relationship between Corvette Racing and the production vehicles. The 2015 Corvette Z06 and new C7.R will be more competitive on the street and track due to successful design of the Corvette Stingray – which itself is heavily based on the C6.R race car.”

Corvette Racing will field two C7.R race cars in 2014, starting later this month at the 52nd Rolex 24 At Daytona on Jan. 25-26. The race kicks off the TUDOR United SportsCar Championship – a new series debuting this year after the merger of the American Le Mans Series and GRAND-AM Rolex Sports Car Series. The C7.R will compete in the GT Le Mans class in 11 races around North America.

The team is also is expected to compete in June at the 24 Hours of Le Mans – a race Chevrolet and Corvette Racing have won seven times – in the GTE Pro class.

Since the team’s competitive debut in 1999 with the Corvette C5-R, Corvette Racing has earned unmatched success. The C5-R and C6.R led Chevrolet to 90 victories around the world and 10 manufacturer championships in the American Le Mans Series. In 2013, Corvette Racing won five races and swept the manufacturer, team and driver championships in the GT class for a second consecutive season.

A key part of the team’s success is the technology transfer between Corvette production cars and race cars.

“Corvette Racing sets the gold standard for technology transfer between the track and street,” said Tadge Juechter, Corvette chief engineer. “We are continually taking what we learn in competition, and applying it to improve production Corvettes – which then make better race cars. As a result, the new Corvette Z06 is the most track-capable production Corvette ever while the new C7.R is poised to be even more competitive on the race circuit.”

Many of the architectural and aerodynamic features of the C7.R are based on equivalent components and technologies from the 2015 Corvette Z06, including:

New, aluminum frame
As before, the race car and the Z06 will share the same, production-based aluminum frame. However, for the first time, the frames for the race car and production Z06 will be built in-house at the Corvette’s Bowling Green, Ky., assembly plant.

By leveraging advanced manufacturing materials – such as laser welding, Flowdrill-machined fasteners and a GM-patented aluminum spot-welding process – the production structure is significantly stronger than its predecessor. For Corvette Racing, this equates to a race chassis for the C7.R that is 40 percent stronger than the outgoing C6.R.

“In the first lap in the C7.R, the drivers felt the increase in chassis stiffness,” said Mark Kent, director of Racing for Chevrolet. “The drivers instantly noticed that the C7.R handling was better over changing surface features and rough track segments. This is important as our drivers don’t always stay on the smooth pavement, and are constantly driving over curbing at corner apexes.”

Direct-injected engine
The addition of direct fuel injection to the Corvette Z06 will enable the technology to return to a Corvette race car for the first time since the end of the GT1 era in 2009. It promises greater efficiency, which can make a significant difference in long-distance endurance racing such as Daytona and Le Mans through fewer time-consuming pit stops.

“Direct injection offers two advantages for the race team,” said Kent. “First, it offers drivers more precise throttle control, so that even the smallest changes in the driver’s throttle position delivers a proportional response from the engine. Second, direct injection typically improves fuel economy about 3 percent. That could be enough to bypass one fuel stop during a 24-hour race. Given that races are often won and lost in the pits, a 3 percent gain in fuel economy could translate to a significant advantage in track position.”

Aerodynamics
The aerodynamic strategies of the Corvette Stingray came directly from the Corvette C6.R – including the forward-tilted radiator, functional hood and front-quarter panel vents, and rear transmission and differential cooling intakes.

The Z06 and C7.R take that aerodynamic foundation to the next level, sharing aggressive strategies for increased cooling and aerodynamic downforce, including similar front splitters, rocker panels, and front- and rear-brake cooling ducts.

“We worked concurrently with the race team developing the aerodynamic packages for the Z06 and the C7.R,” said Juechter. “We even used the same modeling software to test both cars, enabling us to share data and wind-tunnel test results. As a result, the aerodynamics of the production Z06 produce the most downforce of any production car GM has ever tested, and we are closing in on the aero performance of a dedicated race car.”

There are, of course, differences between the race car and production Corvette Z06. For example, the C7.R carries over the powertrain for the C6.R, as the GT rules limit the maximum displacement to 5.5L, and prohibit forced induction. By comparison, the new Z06 boasts a supercharged 6.2L engine estimated at 625 horsepower. Both engines, however, are based on the historic small block architecture.

The suspension on the C7.R is modified to accommodate wider racing tires and larger brakes, again part of the GT regulations.

On the aerodynamic side, one major difference is the shift away from U.S. National Advisory Committee for Aeronautics, or NACA, ducts on the C7.R. The C6.R used two NACA ducts, on top of the rear bodywork and near the position of the rear wheels, for cooling. For the new C7.R, there are now openings on each of the rear quarter panels, above the brake ducts, which will draw air to help cool the race car’s transaxle and differential.

Additionally, one of the primary results of the C7.R’s aero detail is making the rear wing a more-significant part of the car’s aero package. A larger radiator inlet has the added benefit of generating smoother airflow over the rear wing and making its use more efficient to the handling and stability of the race car at high speed.

https://youtu.be/oGiKHLNNBCE

@Big Boss"

The 2015 Corvette Z06 features the industry’s first carbon-fiber torque tube, which provides structural support between the engine and transaxle

A dry-sump oiling system will be standard on all 2015 Corvette Z06s.

The 2015 Corvette Z06 features a standard electronic limited slip differential (eLSD) that continually adjusts engagement of the limited slip to balance between steering response and stability in different driving conditions.

2015 “LT4” 6.2L SC V-8 AFM VVT DI for Chevrolet Corvette Z06

The 2015 Corvette Z06 features an all-new eight-speed automatic, designed and built by GM, that is more than 8 pounds (4 kg) lighter and five-percent more fuel efficient than the six-speed automatic.

@Big Boss"

https://youtu.be/kfhBg5O9i2U

@Big Boss"

https://youtu.be/MHA-btTDPls

[ubengineering]

Things just keep getting better

[misteroman]

^^^^ You still on the gen V line?

[bing]

God Bless…

https://youtu.be/UUvE4TB27L4

In a muted colour with wheels that dont look like shit (like the grey one in the video)… holy hell this thing looks like a hyper car… they could add $40,000 to the sticker price.

[ubengineering]

@misteroman

^^^^ You still on the gen V line?

No LGE, I fill in for maintenance once in a while if they can’t get enough supervisors for OT, but it’s been a couple months.

• • • Updated - - -

Is it just me or is that rear end fucking massive, I can’t even see the driveshaft.

[articzap]

Transmission is bolted to rear end, so that’s probably why lol.

[ubengineering]

@articzap

Transmission is bolted to rear end, so that’s probably why lol.

I was thinking that but didn’t to say it, I mean does it seriously have no driveshaft? Of course I didn’t read all of the above, why read when someone can just tell me?

• • • Updated - - -

One of my workers just told me Corvettes have no driveshafts, not sure if serious…

• • • Updated - - -

After researcing obv not serious, but still curious what exactly I’m looking at up there^

[LZ1]

Corvettes have a torque tube and rear mounted transmission…

[newman]

I’m pretty sure even my Mom knows that.

[ubengineering]

@LZ

Corvettes have a torque tube and rear mounted transmission…

I learned something new today.

@newman

I’m pretty sure even my Mom knows that.

I asked my mom, she knew too! Fuck me!

[articzap]

…

@Big Boss"

(Edmunds)

2015 Chevrolet Corvette Z06 First Look
Behind the Z06 Curtain

The question, says Tadge Juechter, Corvette chief engineer, isn’t how close the 2015 Chevy Corvette Z06 will come to matching the performance of the outgoing ZR1, but rather how badly it will obliterate its performance.

His confidence is reasonable. Because last fall, before the engineering team began tuning the prototype Z06’s engine calibration, springs, stabilizer bars and dampers and using the initial-submission Michelin tires, it broke the existing track record at the company’s Milford Road Course. It was a record held by the outgoing ZR1.

That the record fell is a testament to the fundamental aerodynamic soundness of the car, according to Juechter. That it fell by only 0.1 second means he’s anticipating significant improvement.

New Supercharged V8
Chevy’s new supercharged LT4 (a 6.2-liter V8) will debut in the Z06. The preliminary — and likely conservative — output estimate is 625 horsepower and 635 pound-feet of torque from the new mill. But tradition holds the Z06 is normally aspirated, right?

Not any longer.

A normally aspirated engine couldn’t meet the power, durability and emissions/efficiency requirements Chevy targeted for the Z06, according Juechter. “The only way to make anywhere near this kind of power with a normally aspirated engine is to rev it well beyond 7,000 rpm,” he said. “But that isn’t possible with the Active Fuel Management hardware, which increases valvetrain weight.” As an added bonus, Juechter insists that the final calibration of the LT4 will make the LS9 (the outgoing ZR1 engine) feel like it has no bottom end.

Though it shares its aluminum block with the LT1 (the Stingray engine), the LT4 utilizes a low-profile, low-inertia Eaton supercharger buried deep in its V. Its intercooler blocks are packaged outside the supercharger and are 23 percent smaller than those in the LS9. Despite their size, additional contact area makes them more efficient. In total, the engine is only 1 inch taller than an LT1. Peak boost, at 9.5 psi, is lower than the LS9’s 9.7 psi. Compression is 10.0:1.

Rotocasting yields cylinder heads with stronger material properties, while titanium intake valves, machined rods and forged pistons bring strength to the valvetrain and rotating assembly. Cast stainless-steel headers ensure durability of the exhaust system, and (as in many previous high-performance Corvettes) dry-sump lubrication is standard.

The LT4 is the first production engine in the world to utilize cylinder deactivation in conjunction with supercharging. Like the LT1, it is direct injected and uses variable valve timing.

New Eight-Speed Automatic
Two transmissions are available: a carryover seven-speed manual from the Stingray and a new GM-designed eight-speed automatic. According to Juechter there isn’t a dual-clutch transmission that packages in the Corvette’s rear-mounted transaxle space and can handle the LT4’s torque. Plus, he says, the torque converter improves drivability when in four-cylinder mode, which allows more aggressive cylinder deactivation.

With shift characteristics tailored by the drive mode selector, the new rev-matching automatic is the same size as the outgoing six-speed, but thanks to liberal use of aluminum and magnesium, it’s 8 pounds lighter. It’s also 5 percent more efficient which, when combined with cylinder deactivation (AFM in GM-speak) should make the Z06 one of the most efficient supercars on the market. Accordingly, it’s the perfect choice for a supercar buyer whose purchase decision rests on a green agenda.

Wider, Heavier Despite Lots of Carbon
Wider rubber at both ends necessitates an additional 2.2 inches of front and 3 inches of rear width over the Stingray. Michelin Pilot Sport Cup 2 rubber sized 285/30ZR19 up front and 335/25ZR20 out back will come as part of the Z07 package. Also included in that package are carbon-ceramic brake rotors that are nearly 15.7 inches in diameter up front. They save 23 pounds per car over the standard two-piece iron rotors.

The bulged hood, removable roof panel and ground effects pieces are all carbon fiber.

Possibly the biggest weight-saving measure is the carbon-fiber structural member connecting the engine to the transmission. This 6-foot-long piece endures both drivetrain and chassis loads and is critical in determining the car’s structure and drivability.

Overall weight, however, is higher than the outgoing ZR1, which weighed 3,366 pounds.

Magnetorheological dampers and the electronic limited-slip differential — both of which are optional on the Stingray — are standard equipment on the Z06.

Critical Airflow Management
Look closely at the details and you’ll notice careful management of every molecule passing over, around and through the new Z06. Three levels of aero treatment are available. The first offers a modest front splitter and a modified version of the Z51 rear spoiler. The second increases the size of the front splitter, including the addition of vertical winglets and adds rocker-panel extensions and a mild wickerbill to the rear spoiler.

If the former treatments call into question the car’s street worthiness, the aero additions that come with the Z07 package remove any doubt. It adds larger removable end caps to the splitter’s vertical winglets as well as a large, clear adjustable wickerbill spoiler to the rear. The result is a Corvette with more downforce than any car GM has ever measured in its wind tunnel.

A new physics-defying grille texture allows better flow than an open hole, according to Juechter — a feat we’ll believe when we see proof. Even so, larger transmission and differential coolers, which are packaged in the wider rear-quarter panels are now fed via scooped ducts on top of the fenders. Dedicated brake ducts in the grille draw cooling air over the front brakes, while the now-iconic scoops in the rear fenders perform the same job out back.

Crushing Germans and Italians at a Track Near You
Inside, where the competition sport seats remain optional, the Z06 is similar to a Stingray with wrapped leather surfaces and premium materials. One new interior color (blue) will be available. A unique three-spoke flat-bottom steering wheel is the biggest differentiator from the Stingray.

Probably the biggest news with the 2015 Chevrolet Corvette Z06 is its price. Final pricing isn’t announced yet, but GM insiders insist that its cost will be comparable to the outgoing Z06, which started at $76,595.

“If you could afford the previous Z06, you can afford this one,” said Juechter. Look for the Z06 to hit dealers in early 2015, followed shortly by a mass exodus of Ferraris and Porsches from tracks across the country.

@Big Boss"

Corvette to Feature Two New Colors for 2015

On display at the 2014 North American Auto Show, this 2015 Corvette Z06 that we thought was Cyber Gray turns out to be a new color for 2015. It wasn’t something that jumped out at us until this morning when the show cars were repositioned and the new 2015 Z06 was side-by-side with a 2014 Cyber Gray Corvette Stingray.

We spoke with Corvette Exterior Manager Kirk Bennion about the colors and he confirmed with us that 2014 will be the last year for the popular Cyber Gray. In 2015, the yet un-named color will be take its place.

GM uses different names internally than what we know, and the internal color name is called “Fusion Gray”. Bennion says they are still working on the official name but two names he mentioned are “Shark Gray” and “Tiger Shark Gray”.

You can see the difference between the two colors with the “Shark Gray” being a much lighter shade of gray than the Cyber Gray.

In addition to Cyber Gray going away, we also learned that this will indeed be the last year for Velocity Yellow. Although the new Corvette Z06 and C7.R show car introduced yesterday at NAIAS were Velocity Yellow, the 2015 Z06 will be wearing the new color when it goes into production in late 2014 or early 2015.

However, you will be able to see a preview of the new Yellow which will appear on Corvette Racing’s C7.Rs at Daytona later this month.

The C7.R shown at NAIAS is considered a show car but those in Daytona will be the real deal and they will feature the new yellow. Bennion said they since the C7.Rs were making their official debut in Daytona and throughout 2014, it made more sense to go ahead and race then in the new yellow so it wouldn’t have to be changed next year.

Part of the reasoning is that not only are the C7.Rs Yellow, but so are the three transport trucks, the crew’s tool chests and just about anything with a Jake logo.

The new yellow was described to us as being brighter than the current velocity yellow and we have no doubt that the C7.Rs will wear it well for their 2014 TUDOR USCC campaign.

What do you think of the new Gray and the change in Yellows?

[05OrangeSS]

Bump up

[articzap]

No more ZR1.

That new engine is a significant factor. Though the new LT4 is down on outright power compared to the ZR1, the way it delivers torque is considerably different, offering far more urgency at lower speeds. When run on an engine dyno to calculate power, the graph showing engine torque mapped to RPM sits nearly horizontal. “Even with less power, because there’s more area under the torque curve, it’s so flat, and you spend time sitting at the power peak the whole time, it’s already faster than the ZR1… We haven’t done any straight-line testing, but it’s going to be very close. I suspect it’ll end up faster at every track in the world… That’s our aspiration.”

So, then, with this being the fastest production car GM has ever made, the ZR1 is formally put to rest. It’ll be up to aftermarket tuners, the Lingenfelters and Hennesseys of the world, to try doing even better without ruining the cars they augment. That is, until the next ZR1 rolls around – if it ever does. Juechter is coy about the prospects of the next special 'Vette, but adamant that they held nothing back when creating this one: “We’re not sandbagging. We’re going to do as well as we can on this car and then see about any plans on ZR1…if it’s even possible. We didn’t do a ZR1 in the fifth-generation car. The only reason we did on the sixth generation was because the lifecycle was so long. It wasn’t part of the original plan.”

Profitability, however, is always part of the plan. “There are all these questions to think about before we begin a program which is hellaciously expensive and has to make money. We can’t just do it for fun. It has to make money,” he states emphatically, then ponders for a moment. “As much fun as it would be.”

As we conclude the interview, Juechter gestures to the bright yellow Z06 parked behind him and then displays a keen mastery of the art of understatement. “I think once you drive this, I think you’ll find the power is adequate.”

@Big Boss"

(Road & Track)

8 (More) Things You Need to Know About the 2015 Corvette Z06
Including how to drill holes in it and why the taillights are gray.

I spent some time with Corvette boss Tadge Juechter and his team getting to know the C7 Z06 that debuted in Detroit. It was just us, the yellow show car, and an otherwise empty photography studio. Here are eight things I learned that you won’t find in the press release.

The hidden carbon-fiber torque tube

To make cylinder deactivation work on the Stingray, it needed a stiffer torque tube than the aluminum piece used on the C6. They went with steel, which has three times the stiffness but weighs more. That wouldn’t do for the Z06, so it gets a new carbon piece with aluminum bells on either end. “It looks really cool, and no one will ever see it,” says Juechter.

Michelin has been working on the tires for two years

The tire company bought its own C6 ZR1 to test the new Pilot Sport 2 and Pilot Sport Cup rubber it’s developing for the new Z06. That’s commitment. (And probably a pretty entertaining job.)

Tadge Juechter wants you to drill holes in it

The extra-super-optional aero setup, which is bundled in with the Z07 package (carbon-ceramic brakes, Michelin Pilot Sport Cup tires), comes with an adjustable rear spoiler. The clear piece in the middle is slotted so that owners can move it up and down. But the fasteners holding the opaque pieces together are functional, too. Juechter says you can unscrew them, drill new holes, and get the “authority” (what engineers call adjustability) you want. If it turns out to provide a big bump in testing, GM may even offer an accessory piece with pre-drilled holes. But we just like the idea of the manufacturer telling you to drill holes in your car.

The LT4 is “going to make the old ZR1 seem gutless down low”

So says Juechter. The biggest enabler is a new supercharger, the Eaton R1740. It spins faster than the LS9’s blower (20,000 rpm vs. 15,000) and makes up for its lower displacement per revolution by spinning up quicker and sooner. A little less horsepower, but more torque. We’ll still miss the LS7, but this should make its absence a little easier to handle.

The smoked taillights happened because someone ran out of red tape

Not the bureaucracy-causing kind, but the actual red-hued, adhesive-backed stuff. When the designers were mocking up the car’s details on the clay model, they ran out of red Dynoc. They subbed in gray instead, and when design director Tom Peters saw it, he asked the lighting people if they could make the smoke-gray lenses happen. The answer, obviously: Yes. LED bulbs provide the color when illuminated.

It shouldn’t tramline as bad on the highway

Electric-assist power steering lets them tune that out. So electric steering has an advantage beyond the fuel-economy boost.

They’re not done yet

The car is still a long way from dealers. Engineers managed one day on the Milford Road Course (GM’s proprietary test track affectionately known as the Lutz Ring) in a car that basically came out of computer simulations. First-submission tire formulation, an initial guess at suspension setup and aero, and a powertrain that still has some work left to do. The car will spend the winter doing cold-weather and low-traction testing and then hit tracks—MRC included—when the weather clears. The car may launch at the end of 2014, and significant sales volume won’t begin until the first quarter of 2015.

The next Corvette is always the best Corvette

It’s obvious, but it’s also a kind of mandate for Juechter and his team. He quotes Dave Hill, former Corvette chief and his former boss: “We always have to exceed our previous best.” So the bar gets higher and higher. Which is fine by us.

@Big Boss"

2015 C7 Z06: a Faster, Sexier, Less-Expensive ZR1

The 2015 C7 Z06 will be the fastest production Corvette that Chevrolet has ever built. It will have at least 625hp, and it will probably be a lot less expensive than the C6 ZR1 that was already one of the fastest cars $100,000 could buy. That in itself is no easy task for Corvette engineers, but not only does the C7 Z06 look to completely reset the bar on performance, it was also tasked with broadening the appeal of it’s track-focused machine.

The first real leap from previous Corvette Z06 models is the addition of forced induction. The new 6.2L LT4 direct-injected V8 in the C7 Z06 is expected to produce at least 625hp and 635lb-ft of torque thanks to a new, compact supercharger. Smaller than both the 2.3L supercharger from the ZL1′s LS9 and the 1.9L supercharger from the ZL1′s LSA, the 1.7L Eaton R1740 TVS supercharger in the 2015 LT4 spins up to 20,000rpm, a third faster than the 2.3L TVS used on the LS9. The new, smaller supercharger is able to build boost sooner by spinning faster, and is more efficient for cooler intake charges. The compact size of the rotors allowed powertrain engineers to mount the supercharger low in the lifter valley. The overall height of the LT4 is only one inch taller than the LT1 from the Stingray, keeping the center of gravity low and allowing for a flat hood.

The C7 Z06′s LT4 features several improvements to better deal with the increased cylinder pressure and heat:
-Rotocast A356T6 aluminum cylinder heads are stronger and handle heat better than conventional heads

-Lightweight titanium intake valves and machined connecting rods reduce reciprocating mass

-High 10.0:1 compression ratio – for a forced-induction engine – enhances performance and efficiency; enabled by direct injection

-Forged aluminum pistons with unique, stronger structure ensure strength under high cylinder pressures

-Stainless steel exhaust headers and aluminum balancer are lighter than their LT1 counterparts

The LT4 also marks GM’s first use of Active Fuel Management in a supercharged application. At cruise, the LT4 can run in 4-cylinder mode without boost. Chevrolet engineers told us that during development of the C7 Z06 they tested a tune that kept the LT4 in 4-cylinder mode longer, until the engine developed boost, but it was more efficient to switch back to V8 mode sooner.

Like the C6 Z06, the upcoming C7 Z06 features flared bodywork compared to the car it’s based on. Front fenders are wider by 2.2 inches and cover P285/30ZR19 tires that are 1.5 inches wider than the tires on the Stingray, while the rear fenders stretch 3.15 inches to fit 335/25ZR20 tires that are two inches wider. The new front fascia features front brake cooling ducts on either side of a wider opening that uses a carefully-designed grille that actually increased airflow compared to an empty opening. There’s no question; it looks like it belongs on the track.
To use the power and grip to its potential, Chevrolet engineered a tremendous amount of downforce into the car, with more available in increments depending on the car’s intended use.

-The standard C7 Z06 features a front splitter, spats around the front wheel openings, a unique carbon-fiber hood with a larger vent, and the rear spoiler from the Corvette Stingray’s Z51 Performance Package

-An available carbon-fiber aero package (in either black or a visible carbon-fiber finish) adds a carbon fiber front splitter with aviation-style winglets, carbon fiber rocker panels, and a larger rear spoiler with a fixed wickerbill or “Gurney flap” – a small, vertical tab at the edge of the spoiler that significantly increases downforce

-The available Z07 package adds a larger winglets to the front splitter, along with an adjustable, see-through center section on the rear spoiler for track use; with this package, the Corvette Z06 delivers the most amount of aerodynamic downforce of any production car that GM has tested.

Like the C6 Z06, the C7 Z06 will feature a Z07 option package that marks the pinnacle of track-focused Corvette performance. In addition to the aforementioned aero upgrades, the Z07 brings Michellin Pilot Sport Cup tires, and carbon-ceramic brakes from Brembo with 15.5-inch rotors in the front and 15.3-inch rotors for the rear. That’s up from the 14.6 and 14.4-inch Brembo two-piece steel rotors found on the standard Z06. While the track tuning was not yet complete at the time of our sneak peek, Corvette engineers told us that the C7 Z06 was setting lap records at GM’s Milford Proving Grounds; records previously held by the C6 ZR1.

The final major departure from past Z06 model, the C7 Z06 marks the first availability of an automatic transmission, making it the only 600+ horsepower car on the market with both a traditional manual transmission and an automatic. While the 7-speed Tremec transmission with Active Rev-Match is standard and will likely be popular, Chevrolet told us that the Z06 has to be able to turn a profit in order to earn its keep in the lineup, and a lot of potential Z06 buyers were turned away by the mandatory third pedal. To ensure the widespread appeal of the C7 Z06, Chevrolet engineered an all-new 8L90 eight-speed automatic that offers full manual control via steering-wheel-mounted paddle shifters. The transmission uses a torque converter for smoother shifts, but it’s fast as well, completing wide-open-throttle upshifts eight-hundredths of a second quicker than those of the dual-clutch transmission offered in the Porsche 911. The transmission was engineered to fit in the same space as the existing 6-speed auto, and thanks to creative packaging and the use of aluminum and magnesium, the 8L90 is more than eight pounds lighter than the six-speed it replaces.

The gear ratios for the 8L90 are:
1st: 4.56
2nd: 2.97
3rd: 2.08
4th: 1.69
5th: 1.27
6th: 1.00
7th: .85
8th: .65
Reverse 3.82

Chevrolet has not yet announced pricing, but after the presentation we saw, HOT ROD’s immediate thought was that this would be a $100,000 car like the C6 ZR1, at least. Tadge Juechter, the Corvette’s chief engineer, told us that they’re trying to get the C7 Z06 to undercut the base Porsche 911 that packs 350hp and starts at about $84,000. That’s not much more than a C6 Z06, which would make the C7 Z06 the performance bargain of the decade.

[articzap]

…

@Big Boss"

https://youtu.be/UZD55CO8bOY

@Big Boss"

Yes I did, but I don’t mind posting it again

C6 Z06
2006-6,272
2007-8,159
2008-7,731
2009-3,461
2010-518
2011-906
2012-478
2013-471

C6 ZR1
2009-1,415
2010-1,577
2011-806
2012-404
2013-482

@Big Boss"

(Engine Labs)

LT4 Engine’s Chief Engineer Hints More Power Is Coming

The estimated 625-horsepower figure quoted for Chevy’s new 6.2-liter supercharged LT4 at the Detroit Auto Show unveiling of the upcoming 2015 Corvette Z06 is likely to spiral upwards when the final production model hits the dealerships early next year, according to the engine’s chief engineer.

“We fully expect to beat that number, but we came up with a safe estimate for the show,” boasts Jordan Lee, program manager for GM’s small-block program, also noting that the estimated 634 lb-ft of peak torque should escalate, as well.

The LT4 not only sports a new Eaton supercharger model, but nearly every standard Corvette LT1 engine component was modified, massaged or updated to support the power and packaging goals of the LT4 powertrain team.

“The challenge for us was to add 160-plus horsepower but not get any bigger [than the LT1],” Lee tells EngineLabs. “As remarkable as the LT1 is in power density, the LT4 beats it in droves.”

The LT1, of course, is first of the Gen V small-block engines to hit the market in the new C7 Corvette platform. As EngineLabs demonstrated in previous stories covering the engine’s introduction and an in-depth analysis of the combustion strategy, the LT1 is one of the smallest and most compact engines in the world that is capable of 460 horsepower naturally aspirated. GM wanted to ensure that the engine package didn’t inflate so the Corvette could be offered for sale in Europe.

“We ended up about an inch taller only in the back where the supercharger has an airflow path into the intercooler,” says Lee.

Key to the success of adding boost was working with airflow analysis and development engineers at Eaton to improve the supercharger’s efficiency, even though the blower is smaller than what GM utilized on the Gen IV LS9 engine found in the previous C6 Corvette ZR1. That 6.2-liter engine was rated at 638 horsepower at 6,500 rpm with 604 lb-ft peak torque at a stump-pulling 3,800 rpm.

“The LT4 supercharger is 85mm shorter in height than the one on the LS9, and it weighs 20 pounds less,” says Lee.

Eaton rates the new R1740 TVS supercharger at 1.7-liter, which means it moves that much air with each revolution of the rotors. The previous LS9 supercharger was rated at 2.3-liter.

“We shrunk the capacity down to 1.74 liter,” says Lee, “but we wanted the same airflow characteristics. So we had to spin the supercharger faster.”

The LT4 blower will spin up to 20,000 rpm, compared to the LS9 that maxed out at 15,000 rpm. The smaller rotors also help the supercharger get up to speed quicker, which should boost power earlier in the rpm band.

“We worked a lot of the efficiencies through the supercharger to make sure the airflow was up to the quantity levels needed to make the power,” says Lee.

As with the LS9, there is an air-to-water intercooler integrated into the cast-aluminum intake manifold. But unlike the LS9, the new setup features a clamshell core design with turbolator fins inside the water path compared to a traditional tube with aluminum vanes for the core.

“It’s a very efficient intercooler,” says Lee. “It’s about 23 percent less volume but has 10 percent improvement in heat-rejection efficiency. It’s probably not thee inches long in length but reduces the temperature of the inlet charge by 150 degrees.”

Adding more air requires additional fuel. The Gen V engines feature direction injection with high-pressure feeds coming from a cam-driven fuel pump.

“The biggest challenge was the fuel pump itself,” explains Lee, noting that other exotic DOHC powerplants have up to four pumps to serve the fuel system. “With only one pump we had to increase the size and displacement to handle 625-plus horsepower worth of fuel.”

GM increased the piston size in the pump but didn’t have to change the tri-lobe cam design that drives the pump. Fuel pressure in the lines was increased — the LT1 fuel system operates at nearly 2,200 psi, but no figures were given for the LT4 — and the cylinder heads received larger injectors. The LT1 cylinder ports didn’t need any additional breathing room, but a lighter titanium intake valve was preferred, and the LT1 cast piston was swapped for a forged version that offers a lower 10:1 compression ratio (the LT1 was 11.5:1).

“The 10:1 is still relatively high for a boosted engine,” says Lee, adding that max boost levels will be around 9.5 psi. “We also optimized the camshaft to get the torque and power curves we wanted. The lobe centerline spacing and lift profile are a little different from the LT1.”

The LS9 was also equipped with titanium intake valves as well as titanium connecting rods.

“We didn’t need titanium connecting rods to get the balance we required on the LT4,” counters Lee.

The LT4 features dry-sump oiling, and the oil cooler has been enlarged over the standard Z51 option setup.

In addition to the forged pistons, GM did beef up the entire rotating assembly. The crank is forged with a higher strength steel alloy than the LT1, and the connecting rods are fully machined.

“We added a lot of extra machining on the flanks for light weight,” says Lee. “Also, we annodized the lands on the piston and went with a PVD-coated ring. Finally, the piston pin has DLC coating to handle the extra temperature and pressure.”

Additional durability measures include constructing the cylinder heads with Rotocast A356T6 aluminum and casting the exhaust manifolds out of stainless steel.

Overall, the engine weight will come close to the LS9.

“The 20-pound decrease in the weight from the supercharger offsets the weight from the additional technologies like the DI pump, the cam phaser and AFM. We’ll end up with an estimate round 240 kilograms (529 pounds), which is where the LS9 came in.”

Finally, GM officials refused to speculate on the future availability of an LT4 crate engine when reminded that the LS9 eventually became part of the Chevy Performance catalog. But Lee does offer a reassuring hint: “We pride ourselves on making the small-block available to the aftermarket.”

@Big Boss"

Let me see if I can live up to my elevated status

2010
Coupe-3,054
Convertible-1,003
Total-4,057
Grand Sport-3,707
Grand Sport Convertible-2,355
Grand Sport Total-6,062

2011
Coupe-3,112
Convertible-780
Total-3,892
Grand Sport-5,212
Grand Sport Convertible-2,782
Grand Sport Total-7,994

2012
Coupe-2,820
Convertible-621
Total-3,441
Grand Sport-5,056
Grand Sport Convertible-2,268
Grand Sport Total-7,324

2013
Coupe-2,597
Convertible-720
Total-3,317
Grand Sport-4,908
Grand Sport Convertible-1,736
Grand Sport Total-6,644

From the 2013 end of C6 production:
[I]

This year, GM offered a record 7 different models of the Corvette; the Coupe, the Convertible, the Grand Sport Coupe, the Grand Sport Convertible, the Z06, the ZR1 and the 427 Convertible (a one year model).

The big dog as far as production for the 2013 Corvette was far and away the Grand Sport Coupe with 4,908 units built. This is a repeat performance for the GS Coupe which has been the number one in production since it’s introduction in 2010.

A distant second to the GS Coupe was the standard Coupe with 2,597 units built. Right on the heel of the Coupe was the 427 Convertible with 2,552 units built which knocked out the Grand Sport Convertible that held the 3rd place spot for the 2012 Model Year. Now, the GS Convert settles into 4th place with 1,736 units built.

The last three spots were a bit anemic with 720 Convertibles built, 482 ZR1s built and 471 Z06s built. Many people believe that the 1 year run of the 427 Convertible effected the sales of the Z06 and the ZR1 since this was the only shot to get something close to a convertible version of either of those two super cars.

[articzap]

…

@txsupra11"

Earlier this week at the Detroit Auto Show, Chevrolet introduced its all-new 2015 Corvette Z06 in showroom-glorious Velocity Yellow. But that wasn’t the only example on the automaker’s stand. Opposite the new C7.R racecar sat a completely exposed Z06 – methodically opened to bare all of its detailed mechanicals.

Vehicle cutaway displays offer fascinating insight to the hidden engineering typically buried beneath layers of body panels and glass, so we eagerly snapped and analyzed these pictures of the naked Z06 to share with you. The end result is a high-resolution photo gallery with two dozen images, each carefully captioned to describe the inner workings of Chevrolet’s newest supercar. Click through our gallery for a closer look at the new king Corvette’s inner workings, including its unique carbon-fiber torque tube, exhaust system and suspension engineering – it’s an amazing effort.

2015 Corvette Z06 cutaway allows us to peer beneath the skin - Autoblog

@txsupra11"

With the new 2015 Chevrolet Corvette Z06 that was introduced this past week at the Detroit Auto Show, GM raises the threat level to the bragging rights of virtually every other supercar in the world.
And while performance numbers are still months away, there were plenty of interesting details released with GM’s Z06 announcement—like an all-new ‘LT4’ engine, as well as a new, GM-designed eight-speed automatic transmission designed for exactly this application.

That new ‘8L90’ transmission, designed completely within GM, by a dedicated team, is a traditional hydraulic automatic—solenoids, valves, planetary gearsets and all—but GM says that it provides the super-quick shifts of dual-clutch boxes, yet with more smoothness.

The eight-speed automatic is actually quicker-shifting than the PDK gearbox in the Porsche 911, GM officials say; and that’s a transmission that engineers benchmarked for the project.

“Almost a custom transmission”

Corvette chief engineer Tadge Juechter pointed to some tough packaging challenges. There wasn’t any existing dual-clutch gearbox that could take the torque of the engine and would fit in the space permitted.

“It’s engineered by GM, internally, and many of the parameters were focused on this car,” said Tadge Juechter, at a pre-show event. “So it’s almost a custom transmission.”

“We wanted a transmission that provided everyday drivability and compatibility with cylinder deactivation,” Juechter explained, while they also wanted the speed of a DCT. “When you run in four-cylinder mode, a torque converter is really your friend” in everyday cruising conditions, he said.

The transmission will be used in other applications, Juechter confirmed, but many of the attributes of it were driven by the parameters demanded of the Z06 project.

Also of note is that the transmission offers up to a five-percent fuel economy gain over a six-speed automatic used in the same application

Two-port ‘smart pump’ design a key to being lean and quick

That’s due to a host of engineering changes and analysis of the transmission from scratch, looking at the most efficient path for torque flow. But when we pressed the engineer overseeing the project for the single most important design attribute, he pointed to the ‘smart pump’ setup, in which GM incorporated a binary operation with two inlet discharge ports.

To put it as simply as possible, this clever hydraulic pump system works a bit like the cylinder deactivation the Corvette already has. Under acceleration and aggressive driving, the transmission uses both ports and provides more flow to the clutch packs, to speed up shifts. And then at cruising speed it relaxes to a single port, which reduces drag.

http://www.motorauthority.com/news/1089778_gm-8-speed-in-corvette-z06-shifts-faster-than-porsche-pdk-heres-how

[bing]

Had the distinct privilege of being a few feet away from a dark grey C7 Z06 at the Toronto Autoshow yesterday…

pretty sure i mentioned it earlier that in yellow or red all of the black trim really makes it look busy, but in dark grey it blends well together and honestly makes the Z06 one of the most striking cars i’ve ever looked at. It’s just so fucking gorgeous in the flesh… it really is such a shame that it’s so cheap and will end up in the hands of so many douchebags that shouldnt have something so beautiful.

They should put a Cadillac badge on it and double the price… I’ll be interested to see what front bumper options come out for this though. the only thing that really doesnt do it for me is the lower splitter with the jagged edges.

[ubengineering]

I still can’t get over the exhaust.

[bing]

yeah it isnt that bad in person and i’m sure there will be all kinds of aftermarket options for it that will look awesome.