2009 Chevrolet Corvette ZR1 Thread

[Merc1]

The Devil's Own: GM builds a 620-plus horsepower Super Vette, and trash-talks Porsche, Ferrari, and Lamborghini. Can it walk the talk?


Asked the question, "Why do a ZR1?" Corvette Vehicle Line executive Tom Wallace shoots back, "Because we can. We have the technology inside General Motors to do a car that can go up against any supercar from around the world," he continues, punctuating the thought with this threat: "I can't wait to take on any Porsche with this car, and we're going to be right in there with the Ferrari [599s] and Lamborghini [Murcielagos]." Whoa, ease off the Red Bull, Tom. This is a just a souped-up C6 Corvette, right? Or did you slip a mid-engine V-12 in without the blogosphere noticing?

An hour with chief engineer Tadge Juechter reveals that this is indeed a Z06 upgraded with the best tech in GM's arsenal. A ZR1 was never part of the original C6 plan, but, at an early program review, the Z06's proposed aluminum frame, carbon-fiber parts, and LS7 engine so impressed CEO Rick Wagoner that he reportedly wondered aloud, "Geez, if that's what you can do with $60,000, I wonder what a $100,000 Corvette would look like?" With no more formal authorization than that, Juechter's posse launched a skunkworks effort dubbed "Blue Devil" -- a nod to the boss's Duke alma mater.They started with turbochargers for efficiency's sake, but switched to supercharging when Eaton unveiled its latest four-lobe Roots-type blower. This new unit boasts thermal efficiency of nearly 76 percent (up from some 60 in the best three-lobe blowers) -- near turbo efficiency with no lag.

To preserve forward visibility, the intercooler sends air from the top of the blower out sideways through separate cooling blocks for each bank. There was talk of allowing the blower to stick out through a shaker hood, but water intrusion issues drove the clear polycarbonate window dome.

The engine is based on a modified LS3 6.2-liter block (the LS7's cylinder walls are too thin to withstand boost) and is expected to produce 100 horsepower/liter. Because tweaks are still being made to the cooling system, final testing won't happen for months. (SAE procedures require a 0-to-60 test be run in a car with instruments measuring intake air temperatures at 60 mph so that air can be supplied at precisely the same temperature during the dyno test.) Expect 620-plus horses and around 600 pound feet.

Because blowers add weight, extensive lightening efforts were concentrated in front. The fenders, hood inner and outer panels, roof panel, and C-pillar roof bar are carbon fiber, the tooling for which caps production at 2000 per year. The fibers are visible on the roof and hood inner, and to prevent ultraviolet light from degrading them a special additive costing over $60,000/gallon (!) is added at three-percent concentration in the thin clear-coat layer ($2000/gallon). In all, the new car is expected to weigh about 200 pounds more than a Z06 and to nudge the weight bias forward slightly to 52/48 front/rear.

Major developments in the chassis department include Brembo calipers grabbing gigantic carbon-ceramic rotors designed for Ferrari's Enzo and FXX. (At an expected price of near $100,000, the ZR1 will be the least expensive car with standard CCM brakes.) We're assured the brakes work perfectly well when cold, and they don't squeal. Delphi reengineered its magneto-rheological shocks to withstand the extreme temperatures encountered in track duty, allowing the ZR1 to ride like a base coupe and outhandle the Z51 and Z06.

Will it all work? The ZR1 is undergoing GM's full battery of passenger-car durability tests as well as its motorsport torture regimen (250 miles of autocrossing and a 24-hour endurance race), so it should hold up fine. The hardware and numbers sound impressive and we're rooting for the home team, but can a car with a front weight bias really smoke a GT3 or F430 Scuderia around the 'Ring? And if it does, will the well-heeled queue up to buy one?

WHY ZR1?

"Deciding on a name turned out to be one of the hardest parts of the project," Tom Wallace admits. ZL1 was considered, in recognition of the ultrarare 1969 aluminum big-block package (just two were sold). Z07 was postulated, but then, this car is more than "one better than a Z06," so that was rejected. Saint Zora himself said that "all Corvettes are Super Sports," so SS never got much traction. Blue Devil is fraught with meaning inside GM, not out-but it served as great inspiration for all the blue trim accents. Which left ZR1 as the most sensible choice. This is, after all, a spiritual successor to the C4 ZR1 of 1990. That car sold for the equivalent of $91,000 2007 dollars and represented the state of the automaking art at General Motors in its day. So does this one.

Among the ZR1's many impressive aspects is that it wasn't developed by a nameless engineering squad numbering thousands. It was etched out by a small team of gung-ho gearheads who've worked on this thing 24/7 for the last few years. Gotta like that. We'll have to hold our horses a bit until that all-important first drive, which is several months off yet. It appears worth the wait, however, as the fastest, highest-tech, and perhaps the most unique.

HOW RICK WAGONER ASKED THE RIGHT QUESTION

MT: WAS THE ZR1 YOUR IDEA?

WAGONER: I was part of a group, but the question came up: "There's been so much enthusiasm for the Z06, is this the most we could do?" I think it got the Corvette team thinking of the so-called super-Corvette. So if I have been given any credit, it would be more of that sort of observation: It's such a great brand, is there anything more we can do with it? Actually, to give credit where it's due, this conversation may have arisen with one of our board members.

MT: SO WERE YOU THE GUY WHO RAISED HIS HAND?

WAGONER: Success has many fathers. But I did ask the question. It's not the kind of thing where everybody went: "Oh, no, we don't want to do that." It was kind of like putting gasoline on a fire.

MT: BUT IT'S ALSO SOMETHING YOU WOULDN'T HAVE DONE 10 YEARS EARLIER.

WAGONER: The momentum around the product has got everybody thinking about it more. So it's created an environment. But what the Corvette team has done so well is they've brought out different variations of the car in a successful way. Successful in that first they built the brand; second, they appealed to the lovers of the car; third, it's been a financially attractive strategy. I like all three of those.


CAR DETAILS

1. Carbon fiber front fenders feature unique "gills" (pictured at right)

2. Carbon fiber hood (pictured below) includes 19"x17" polycarbonate "window," through which supercharger intercooler casting is visible (window treated like headlamp-covers to resist scratching and ultraviolet light)

3. Underside of hood is clear-coated carbon fiber with no hood insulator pad. The hood just barely clears the engine. There's no pedestrian impact clearance

4. Front fascia is Z06 carryover-there's no further aero or cooling improvement to be had

5. Carbon fiber chin spoiler/splitter protrudes 4" (up from Z06's 1"), helps reduce lift, directs air toward control-arm-mounted fins that aim it toward the brakes (pictured below)

6. Carbon fiber rocker extensions carry the motif rearward; rear fascia unchanged from Z06's

7. Roof panel and roof bow cover both clear-coated carbon fiber-best way to identify a ZR1 from afar. Roof panel saves 6.6 pounds relative to Z06 panel

8. Full-width rear spoiler works with front splitter to balance lift, so handling behavior doesn't change at higher speeds

9. ZR1 will offer one upgrade package, consisting primarily of the hand-sewn Draexlmaier leather interior and navigation, priced around $10,000

10. Interior gets ZR1 embroidery on seats, boost gauge in the cluster


ENGINE DETAILS

1. Eaton TVS R2300 (Twin Vortices Series, 2.3 liters per supercharger revolution) blower, pictured at right, produces 10.5psi of boost at up to 76 percent thermal efficiency (up from 60 percent on previous designs). Also produces less whine

2. Intercooler routes high-pressure air sideways through two air-to-water coolers rather than up through a single one to lower the hood line. System's one-gallon dedicated cooling circuit lowers charge temperature by 108 degrees F (pictured below)

3. Basic 6.2-liter LS3 block reinforced primarily in the second and fourth bulkhead areas, improving its safety factor by 20 percent

4. Four-layer steel head gasket (up from two layer) permits more "lift" under peak loads

5. Increased clamping load on cylinder heads requires 12mm bolts, up from 11mm

6. Cylinder head material upgraded to A356-T6 aluminum-silicon alloy to better handle the high heat between the valves, and the mold is rotated while the metal is poured into it, reducing porosity

7. Intake runner in cylinder head includes a port swirl wing to improve combustion. Slight restriction it causes is easily overcome with boost pressure

8. 55mm titanium intake valves; 44.4mm hollow sodium-filled exhaust valves

9. Pistons provide no clearance for valves, 9.1:1 compression ratio

10. Titanium connecting rods, similar to Z06's

11. Crankshaft is forged of microalloy steel 44MnSiVS6

12. Flywheel attaches with nine bolts, up from Z06's six

13. Special dual-pressure fuel module delivers fuel at 87 psi under high load (max flow rate is 1.2 gal/min), 36 psi at idle and low load

14. Fuel is delivered to the center of each fuel rail for more even pressure distribution

15. Premium unleaded will be required

16. Supercharger shares serpentine belt with power steering and water pump. Belt upsized to 11-rib design, water-pump bearing enlarged from 16 to 19mm to withstand force

17. Oiling system is dry-sump, like Z06's, but includes second auxiliary tank to feed the oil pickup during peak (1.6g) cornering events. Total capacity is 10.75 qts

18. Oil cooler is mounted to the oil pan


2009 Chevrolet Corvette ZR1 - Exclusive First Look - Motor Trend


M

[Merc1]

Press Release:

CHEVROLET ENTERS THE WORLD OF SUPERCARS WITH 2009 CORVETTE ZR1

New, Supercharged LS9 V-8 is the Heart of the ZR1

DETROIT - Chevrolet officially announced the 2009 Corvette ZR1 - an American supercar that brings the technology and engineering refinement of carbon-fiber, ceramics and electronics together in a distinctive design.

“Chevrolet’s goal with the new ZR1 is to show what an American supercar can deliver, at a price that trumps exotics that cost two, three or four times as much - and does so with exceptional driveability,” said Ed Peper, Chevrolet general manager.

The ZR1’s basic stats:

- All-new LS9 supercharged 6.2L V-8 targeted at producing at least 100 horsepower per liter, or 620 horsepower (462 kW), and approximately 595 lb.-ft. of torque (823 Nm)
- Six-speed, close-ratio, race-hardened manual transmission
- New, high-capacity dual-disc clutch
- Higher-capacity and specific-diameter axle half-shafts; enhanced torque tube
- Specific suspension tuning provides more than 1g cornering grip
- Twenty-spoke 19-inch front and 20-inch rear wheels
- Michelin Pilot Sport 2 tires - P285/30ZR19 in front and P335/25ZR20 in the rear - developed specifically for the ZR1
- Standard carbon-ceramic, drilled disc brake rotors - 15.5-inch-diameter (394-mm) in the front and 15-inch-diameter (380-mm) in the rear
- Larger brake calipers with substantially increased pad area
- Standard Magnetic Selective Ride Control with track-level suspension
- Wider, carbon-fiber front fenders with ZR1-specific dual vents
- Carbon-fiber hood with a raised, polycarbonate window - offering a view of the intercooler below it
- Carbon-fiber roof panel, roof bow, front fascia splitter and rocker moldings with clear-coated, exposed carbon-fiber weave
- ZR1-specific full-width rear spoiler with raised outboard sections
- Specific gauge cluster with boost gauge (also displayed on the head-up display) and 220-mph (370 km/h) speedometer readout
- Only two options: chrome wheels and a “luxury” package
- Curb weight of approximately 3,350 pounds (1,519 kg)

The specialized components of the new ZR1 work harmoniously to deliver the most powerful and fastest automobile ever produced by General Motors. Performance estimates will be announced closer to vehicle’s summer 2008 launch.

“Preliminary testing shows the ZR1 builds on the highly respected Corvette Z06 in every performance category, from acceleration and braking, to cornering grip and top speed,” said Peper. “It all boils down to the power-to-weight ratio and the ZR1’s is exceptional - better than the Porsche 911 GT2, the Ferrari 599 and even the Lamborghini LP640. In fact, the ZR1 is expected to be the first production Corvette to achieve a top speed of at least 200 mph.”

Supercharged LS9 engine

The new LS9 6.2L small-block engine is the power plant the supports the ZR1’s performance capability. The enabler of the LS9’s performance and refinement is a large, positive-displacement Roots-type supercharger with a new, four-lobe rotor design. It is augmented with an integrated charge cooling system that reduces inlet air temperature for maximum performance.

A sixth-generation supercharger developed by Eaton helps the LS9 make big power and torque at lower rpm and carries it in a wide arc to 6,600 rpm, as it pushes enough air to help the engine maintain power through the upper levels of the rpm band - the area where supercharged performance tends to diminish. Heavy-duty and lightweight reciprocating components enable the engine’s confident high-rpm performance.

The LS9 is hand-assembled at GM’s Performance Build Center, in Wixom, Mich., and incorporates specialty processes typically seen in racing engines to produce a highly refined and precise product. For example, cast iron cylinder liners are inserted in the aluminum block and are finish-bored and honed with a deck plate installed. The deck plate simulates the pressure and minute dimensional variances applied to the block when the cylinder heads are installed, ensuring a higher degree of accuracy that promotes maximum cylinder head sealing, piston ring fit and overall engine performance.

Transmission and axle

The LS9 engine is backed by a new, stronger six-speed manual transmission and a twin-disc clutch that provide exceptional clamping power, while maintaining an easy clutch effort. ZR1-specific gearing in the transmission provides a steep first-gear ratio that helps launch the car, and top speed is achieved in sixth gear - a change from the fifth-gear top-speed run-outs in the manual-transmission Corvette and Corvette Z06.

As the term implies, the twin-disc clutch system employs a pair of discs, which spreads out the engine’s torque load over a wider area. This enables tremendous clamping power when the clutch is engaged, while also helping to dissipate heat better and extend the life of the clutch.

The twin-disc clutch system also contributes to the ZR1’s exceptional driving quality, with smooth and easy shifting. The twin-disc system’s design enables a 25-percent reduction in inertia, thanks to smaller, 260-mm plates, corresponding to a pedal effort that is similar to the Corvette Z06’s 290-mm single-disc system.

The rear axle also is stronger in the ZR1 and features asymmetrical axle-shaft diameters that were developed after careful testing to provide optimal torque management. The axles are also mounted on a more horizontal plane that correlates with the wider width of the rear wheels and tires.

Ride and handling

The ZR1 is built on the same aluminum-intensive chassis as the Corvette Z06 and features similar independent SLA front and rear suspensions, with aluminum upper and lower control arms. Where the ZR1 differs is the suspension tuning, which was optimized for the car’s steamroller-wide front and rear tires.

Magnetic Selective Ride Control is standard and tuned specifically for the ZR1. The system’s ability to deliver a compliant ride with nearly instantaneous damping adjustments enabled engineers to develop a surprisingly supple ride quality in a supercar that still delivers cornering grip of more than 1g.

From a high-performance perspective, Magnetic Selective Ride Control helps the rear axle remain planted during launch for smooth, hop-free acceleration. It also helps suppress axle movement when cornering on broken or uneven pavement.

Brakes, wheels and tires

Commensurate with the ZR1’s engine output is the braking system, which is headlined by carbon-ceramic brake rotors. Found on only a few exotics and more expensive supercars, carbon-ceramic brake rotors are made of a carbon-fiber-reinforced ceramic silicon carbide material . Their advantage comes in low mass and resistance to wear and heat. In fact, the rotors should never show any corrosion or require replacement for the life of the vehicle, when used in normal driving.

The vented and cross-drilled rotors on the ZR1 measure 15.5 inches (394 mm) in diameter in the front and 15 inches (380 mm) in diameter in the rear - making them among the largest carbon-ceramic rotors available on any production vehicle.

Clamping down on the high-tech rotors are six-piston front calipers and four-piston rear calipers, each painted a ZR1-exclusive blue. The front pads are equivalent in size to the largest on any production car with a single-pad design - double that of the Corvette Z06’s 70-sq.-cm. front pads.

The brakes are visible through the ZR1’s exclusive wheels: 20-spoke alloy rims that measure 19 inches in diameter in the front and 20 inches in the rear. They come standard with a bright, Sterling Silver paint finish and chrome versions are optional. The wheels are wrapped in Michelin Pilot Sport 2 tires developed specifically for the ZR1, measuring P285/30ZR19 in front and P335/25ZR20 in the rear.

Exclusive exterior

The ZR1 is instantly recognizable, with perhaps the most identifiable feature a raised, all-carbon-fiber hood that incorporates a clear, polycarbonate window. The window provides a view of the top of the engine’s intercooler, with the legend “LS9 SUPERCHARGED” embossed on the left and right sides, and an engine cover with the Corvette crossed flags logo debossed at the front.

The underside of the hood has an exposed carbon-fiber-weave. Exposed carbon-fiber is used on the roof, roof bow, rocker molding and front splitter. These exterior components are protected by a specially developed glossy, UV-resistant clear coat that resists yellowing and wear.

Widened, carbon-fiber front fenders with specific, dual lower vents, and a full-width, body-color rear spoiler incorporating the center high-mounted stop lamp, are also unique to the ZR1. All of the exterior features of the car were developed to enhance high-speed stability and driver control.

Interior details
The ZR1’s interior builds on the brand’s dual-cockpit heritage, with high-quality materials, craftsmanship and functionality that support the premium-quality experience promised by the car’s performance. The ZR1’s cabin differs from the Corvette and Corvette Z06 with the following:

- ZR1-logo sill plates
- ZR1-logo headrest embroidery
- Specific gauge cluster with “ZR1″ logo on the tachometer and a 220-mph (370 km/h) readout on the speedometer
- Boost gauge added to the instrument cluster and Head-Up Display

The “base” ZR1 (RPO 1LZ) comes with accoutrements based on the Z06, including lightweight seats and lightweight content. The uplevel interior package includes unique, power-adjustable and leather-trimmed sport seats (embroidered with the ZR1 logo); custom, leather-wrapped interior available in four colors; navigation system, Bluetooth connectivity and more.


Officially Official: 2009 Chevrolet Corvette ZR1 debuts before Detroit


Looks like the European supercar establishment has a real problem, at least on paper.

M

[Deutsch]

Yet another monumental product from GM. And we haven't even seen the production 5thgen Camaro.

[Kowalski]

620 Hp?!

Move over 599 GTB!

[zetableh]

I can't wait to see Top Gear get their hands on this. Hopefully GM will send them one with the pretty interior so they have nothing to kvetch about!

[Kowalski]

Originally Posted by zetableh

I can't wait to see Top Gear get their hands on this. Hopefully GM will send them one with the pretty interior so they have nothing to kvetch about!

Of course they will "kvetch" about:

-The interior.
-The poor ride (presumably).
-The flimsy body.
-It's American... everybody hates Americans.
-It's a Corvette = Uncool (Legend but suffers of a terrible image).
-Left hand drive only.

[Sunny]

Not a fan of that see through hood cover. But who cares, it will kick some very serious European butt. Move over GT2 and Scuderia.

[audi_rudy]

This car will murder anything and all that for 100K, you have got to be kidding right
620 Hp in this car is going to be ridiculous the GT2 was nicknamed the widow maker but I think we have found a new one. All this great stuff but sorry I would never buy one I dont like the looks, interior or anything about it really, but that dosent mean i dont respect it for its amazing performance.

[Merc1]

Forget the King of the Hill. Meet the God of the Mountain


You've waited long enough to hear the real deal on the 2009 Chevrolet Corvette ZR1, right? The nonstop, server-frying deluge of speculation, hoaxes, misinformation, wild-ass guessing and publicity-stunt silliness has dragged on just short of three years now.

In anticipation of the ZR1's introduction at the 2008 Detroit auto show in January, Chevrolet at last has opened the proverbial hood on this, the most powerful, most expensive and most highly anticipated Corvette in the model's half-century history.

Here, finally, is the real story.

"Greater Than 620 Horsepower"

All right, so there's one thing that we can't put a final figure to and that's the important one: the ZR1's power output.

But Ron Meegan, the assistant chief engineer for the new 2009 Chevrolet Corvette ZR1's supercharged V8 (and formerly a member of the original ZR-1's engine team from 1990-'95), says he expects that once the new car's supercharged 6.2-liter V8 is certified, it will produce "greater than 620 horsepower at 6,500 rpm and 595 pound-feet of torque in the 3,600-to-4,000-rpm range, depending on some last-minute tuning items."

So even GM doesn't have a final power figure yet. Although you can be sure that if Meegan's superiors allowed him to mention any figure to us, they're not worried about making those numbers. Remember, when the current-generation Z06 was unveiled, it came with a claim of 500 hp, and when the production car arrived it had a rating of 505 hp.

Whether the ZR1 is rated at 625 hp or 633 hp or whatever, it won't just be the most powerful Corvette production vehicle ever (including ones measured by the grossly overstated "SAE gross" figures of pre-1972), it won't even be close. The power produced by the ZR1's LS9 engine will be roughly the equivalent of three 1980s-era Corvette small-block V8s bolted together. It'll produce more power than the Corvette C6.R that races at the 24 Hours of Le Mans.

The Nordschleife on Chrome Rims, Y'all

ZR1 chief engineer Tadge Juechter says, "If a buyer really wants them, he can get chrome wheels on it," although he's letting us know that he would never do such a thing and he thinks you shouldn't either. But the ZR1 isn't a racecar.

Think of the Corvette lineup in Porsche 911 terms. The base coupe and convertible Corvette are analogous to the standard Carrera and Carrera S. The Z06 is the GT3 — the loud, hard-core choice of the performance junkie. The ZR1 is the Porsche Turbo. It's devastatingly fast, but it's also intended to be civilized. It's available with a head-up instrument display, power-adjustable seats, high-end audio and Delphi's smooth-riding MagneRide suspension dampers. It's no raw-boned racer. Hell, at 3,300 to 3,400 pounds, the ZR1 is almost 300 pounds heavier than a Z06.

Juechter adds, "It's sort of like the Turbo but for less money and with performance — more like the Carrera GT."

That's big talk. But, while Chevrolet is not yet making specific performance claims, Juechter notes that the ZR1 will be faster, quicker and more responsive in every way than a Z06. "You won't see a huge difference in 0-60 mph because even the Z06 is traction-limited through most of that," he says. "But in the quarter-mile and tests from zero to 100 mph to zero, there will be big differences."

And just to up the ZR1's chest-puffing quotient, Juechter notes this car "will be able to take the production-car track record at any racetrack." Ex-squeeze me? And no, the company has not done an officially timed run at the Nürburgring yet.

As for top speed, Juechter says only that the 200-mph speedometer of the standard and Z06 Corvettes has been replaced with a 220-mph unit, because the standard one is "grossly inadequate."

Hot Wheels

By now you probably have noticed that the ZR1 looks like, well, a C6 Corvette. The silhouette is, of course, the same and the overall dimensions are essentially identical to a Z06.

But there's a goodly helping of racecar bluster applied to this vehicle. It's hard to miss the hole in the hood that measures roughly 19 by 16 inches, for example. A clear polycarbonate window lets you see the intercooler cover with its fancy script. This is the ZR1's signature styling flourish. Truth be told, it's a bit Hot Wheels for our tastes. The hood is made from carbon fiber, and while the exterior has been painted, the underside retains its carbon-fiber's undressed matte finish.

The front fenders with their ZR1-specific twin-port gills are also made from carbon fiber. The prominent aerodynamic front splitter is — you guessed it! — carbon fiber. It sticks out proud of the nose by 4 inches at the edges, making it a dandy place to rest your Hummel figurine collection. Clear-coated carbon rocker extensions make the vehicle look almost subterranean. The top and B-pillar are covered in clear-coated panels of the stuff as well. This car will look wicked in black.

According to Juechter, GM has used a special super-secret additive to the clear coat to protect the unpainted carbon from the sun's ultraviolet rays. (UV rays can break down the resin that helps give carbon fiber its stiffness.) He claims that the substance costs $60,000 per gallon. But since the clearcoat needs only 3 percent of the stuff, the resulting clearcoat costs merely an absurd $2,000 per gallon. This mystery material was originally designed to protect circuit boards from UV. Juechter acknowledges only that the substance has no chemical similarity to mayonnaise and says, "We should probably not imply that it is edible anyway."

The front aero splitter is matched in the rear by a spoiler of a relatively modest height that is taller at the edges than in the center, a measure to combine an optimum balance between a decrease in aerodynamic lift and an increase in aerodynamic drag.

The wheels are a new design produced by Speedline, measuring 20-by-12 inches in the rear and 19-by-10 inches up front. They are covered (barely) by Michelin Pilot Sport PS2 tires, specifically formulated for this vehicle. At 335/R2520, the rear tires resemble something you might find in a steamroller; the fronts are a not-much-more-modest 285/R3019.

The interior is essentially identical to the regular Corvette. ZR1 badging and a boost gauge in place of the voltmeter are the only changes to the cabin.

Traction Limited

Even with the gigantic meats bolted to the backside, the ZR1 will be what is euphemistically called "traction limited." In other words, all that power just goes up into expensive smoke when you try to lay the power down.

And since launching a car with so much horsepower can become a violent, axle-hopping mess, Chevrolet has come up with two novel countermeasures.

First are the rear shocks. When you're stopped and the clutch pedal is depressed and you pile on some revs, the car assumes you want to launch it hard. It automatically softens the compression damping of the rear shocks, and this allows the rear end to squat and effectively shift more weight to the rear of the car for added traction. At the same time, the rebound damping of the rear shocks goes up to 99 percent of full stiffness. This means that the rear cannot spring back up under power in the up-and-down monkey motion of axle hop.

All this is perhaps the cleverest use of adjustable shocks that we've ever heard of. Also, according to Juechter, the standard magnetic shocks allow the ZR1 chassis team to use softer springs than the Z06 for a more compliant ride. To further mitigate power hop, Chevy has also fitted the ZR1 with axle half-shafts of different diameters (33mm on the right and 40mm on the left).

We'll see how all of this works next year when we finally get to drive the thing. We might just try a hard launch or, you know, several.

Stop, I Say

There should be no dispute about the effectiveness of the ZR1's brakes. The rotors are as large as or larger than most wheels were just a decade ago.

In what must be a very sweet moment for a longtime Corvette engineer, Juechter notes that the monster 15-inch Brembo carbon-ceramic rotors fitted as standard to the ZR1's rear wheels are the brakes originally designed for the front of Ferrari's 650-hp Enzo supercar. In the front of the ZR1, you'll find even larger 15.5-inch carbon-ceramic units.

Juechter says, "The only vehicle I know of that has these brakes as standard equipment is the 1,000-hp Bugatti Veyron." Then he adds with a grin, "Although I think you can get them as a $20,000 option on the Ferrari 599." We get the sense Juechter will be using these laugh lines many, many times in the near future.

The Price of Production

Chevrolet isn't about to tell us the price it intends to charge for the 2009 Chevrolet Corvette ZR1. But it tells us that the prime motivator for the project has been GM honcho Rick Wagoner, who asked, "What would a $100,000 Corvette look like?" The ZR1 is apparently the answer and we expect the car's list price will be near enough to the $100,000 mark.

Chevy says it is constrained by production of the carbon-fiber bits to only 2,000 ZR1s per year, and since it seems to us as if we've met almost as many Corvette nuts in our career with the funds to bid up the price significantly, we think the list price might be strictly academic in the first year's production.

So that's it. There's no more mystery Corvette. We'll have to just go ahead and go through the arduous task of driving the thing and testing it.

Shortly thereafter we'll begin speculating on the C7 Corvette and the circle of life will continue.


First Look: 2009 Chevrolet Corvette ZR1


M

[The Artist]

damn thats hot..this car will eat alot of others ALIVE

[Merc1]

Inside the Supercharged 620-hp LS9 V8


GM isn't just kidding around with the supercharged 620-horsepower V8 that's at the heart of the 2009 Chevrolet Corvette ZR1.

It'll produce more urge than the absurdly powerful twin-turbocharged Mercedes V12 or the race-bred V10 of the Porsche Carrera GT or nearly any other internal combustion engine ever produced for vehicular transport. Most important, the 2009 Chevrolet Corvette ZR1's V8 makes more horsepower than the Dodge Viper's new 8.4-liter V10.

And it will carry GM's 100,000-mile powertrain warranty when the ZR1 goes on sale next fall as a 2009 model.

That's Just Super!

The secret to this ridiculous power output figure is no secret at all. It is in large part the doing of the Roots-type supercharger, one of the oldest tricks in the engine builder's book. More than a century after it was devised, this fundamentally simple air compressor helps Chevy's pushrod small-block (itself devised more than half a century ago) develop at least 100 hp per liter.

For those challenged by arithmetic, this means the displacement of the ZR1's engine is 6.2 liters, the same size as the V8 of the standard 2008 Corvette. But, you say, "Why wouldn't they throw the supercharger on the 7.0-liter Z06 motor and make, like, a million horsepower?" But Ron Meegan, the assistant chief engineer for the new 2009 Chevrolet Corvette ZR1's supercharged V8, replies, "The LS7 is a pretty polished beast. There's not much more to be had there."

Also there's the little issue of block strength. As it is, the 6.2-liter block, which is the same physical size as that of the 7.0-liter, had to be substantially strengthened for supercharged duty. Overall, the LS9's block is 20 percent stronger than that of the standard LS3.

Why not turbocharging? "Well," says ZR1 chief engineer Tadge Juechter, "we built a turbo car and it burned. We didn't want to get into turbo lag or any drivability issues. We wanted it to be quicker than hell but still fun to drive."

More Lobes, More Power

Juechter tells us that supercharging has been more important to the project than you might realize. He says, "Honestly, had Eaton not come up with this new, more efficient, sixth-generation supercharger, we might not have done the car at all."

Meegan tells us that Eaton's Twin Vortices Series (TVS) supercharger uses four-lobe rotors in place of the conventional three-lobe units, making it quieter and more efficient. The parasitic loss to drive the supercharger is around 70 or 80 hp, but it would have been more like 120 hp with the old supercharger, Juechter says. For the LS9, the supercharger cranks out 10.5 psi of boost.

And for those of you who dream of swapping out the stock supercharger pulley to make like a billion horsepower, be aware that Meegan says, "We don't want people to do that. We have not made that easy."

Wild Ride

The air molecules lucky enough to get sucked into the ZR1's V8 take a pretty straight shot through the intact tract, through the air filter, throttle body and into the supercharger inlet, nestled between the V8's cylinder banks. After that, things get a little circuitous.

The intake air molecules then get squeezed through the counterrotating rotors that look like gigantic black licorice twists. It then gets pushed up through a triangular hole in the top of the supercharger housing in between two long, narrow intercoolers. A 90-degree turn either left or right leads our molecular heroes to an intercooler that Meegan claims can lower the air temperature by 140 degrees F. The intercoolers are connected to a heat exchanger in the car's nose and filled with standard-issue antifreeze.

Once through the intercoolers, the now-chilled air takes another 90-degree turn down into the left or right cylinder bank of the engine. Here it will enter a combustion chamber (the compression ratio is 9.1:1) through intake valves that have the same diameter as those in the heads of a standard LS3 V8. The LS9's intake valves are made with lightweight titanium, however, and are set in cylinder heads made from high-strength aluminum.

Sandwiched between the heads and the block are head gaskets twice as thick as standard LS3 gaskets in order to cope with the upward force that's trying to send the heads through the hood. Upgraded fuel injectors are connected to a dual-pressure fuel delivery system (low pressure for low throttle load situations; high pressure for high load). New forged-aluminum pistons (cooled by oil squirters) are connected by titanium rods to the steel crankshaft.

Spent air exits through exhaust manifolds identical to those on an LS7 motor and through 3-inch exhaust pipes capped off by vacuum-actuated flaps as seen on the Z06. The LS9's oiling system is similar to that of the Z06's LS7 as well. It uses the same dry sump as the LS7 but has an additional 2.75-quart auxiliary tank that helps keep oil where it needs to be in a car that Juechter says can post lateral acceleration figures "comfortably over 1g."

It might seem strange, but the LS9 uses a lower-lift cam than the one used in the LS7, resulting in an idle that Meegan says is 11 percent smoother. Isn't this the baddest, leanest, most extreme, track-scorching, widow-making Vette from hell? Well, apparently, no.

Power Delivery

The monster motor is backed by a six-speed manual transmission that is a strengthened version of the TR6060 transaxle used on the standard '08 Vette.

This is a true close-ratio unit, unlike those of other Vettes, and 6th gear is no longer a fuel-saving ratio but instead the gear in which top speed can be achieved. "This buyer says, 'I can buy the gas. Just give me the performance,'" says Juechter.

A twin-plate clutch replaces the standard single-plate of all other Corvettes to handle the extra power and keep clutch pedal effort roughly equal to that of the Z06.

Show and Tell

Chevrolet is sufficiently proud of this supercharged small-block to give it its own window in the hood of the 2009 Chevrolet Corvette ZR1. In fact, the ZR1's signature feature is this clear polycarbonate porthole that reveals the LS9's integrated supercharger/intercooler unit. That should leave no doubt about which element of the ZR1 is most important.

We would imagine that the company could find more uses for this admittedly expensive powerhouse. Maybe GM should put it into all the Cadillac CTSs, Cadillac XLRs, Chevrolet Camaros, Pontiac G8s and — what the hell — everything else the company builds. If you believe Mr. Robert Lutz, GM's product potentate, future CAFE standards will kill all but the lowest-volume, highest-priced performance cars in the world.

Neither Meegan nor Juechter gave us fuel-economy estimates on the ZR1 and we didn't bother to ask.

2009 Chevrolet Corvette ZR1's V8

M

[Deutsch]

The interesting thing about the ZR1 is that they set the suspension to be softer than the Z06, because complaints that the latter could easily end up as a handful when driven enthusiastically. One of the main goals for the ZR1 was to make it easier to drive than the Z06 and easy to drive fast. Hopefully they accomplished that because a lot is at stake here with such an incredible amount of power being put down all at the rear wheels.

[DocM]

Respect to Chevy, it took them a while to wake up!
Now if they'd only remembered to tidy up that awful interior.

I think it's safe to assume that the ZR1 is the least expensive 620 hp car out there.

And, nissan with the GT-R also offer a great bang for your buck.
Germans, it's time to rethink your asking price

[Merc1]

I didn't see this earlier, but the roof panel and pillar trim are carbon fiber:



M

[PanterroR]

[Just_me]

bye bye Skylie GTR

N-ring 7.30 min...

[DeDe]

Looks pretty damn good, and (after the Z06) I have to say this will be a great performance car!

btw: Why is it a '2009-model'? I still don't get it...

[Merc1]

Well it doesn't go on sale until the fall of 2008, making it a 2009 model by U.S. standards.

M

[Centurion]

Monstrous, but does it have launch control or something to help get all that power down to the ground?

[Merc1]

Nope, just 12 inch wide rear tires!!!

M

[Just_me]

Is it running on runflats?

[Merc1]

No. There is no mention of runflats.

M

[Bruce]

I wouldn't be too sure of the ZR-1 humiliating the GT-R. There's little doubt that ZR-1 will be a monster (and a fantastic sports car), but on a track like the Hockenheim I wouldn't be surprised if the GT-R was able to fend off the 'Vette. Do take note that the Skyline will have the great advantage of traction (notably thanks to it's drive train and control sysyems) and thus is obviously something which most 'Vettes seem to (understandably) lack.

Nor would I would be the least bit surprised if the GT-R had the advantage off-the-line. Sure, by and large the ZR-1 will undoubtedly be faster in a straight line, but will it really been able to pull it's weight on the circuit?

And yes, I'm fully aware of the Z06's amazing set of figures in Sport Auto's Supertest. Look at it this way - the Zonda may be a lot lighter than the Carrera GT and it may have a boatload more thrust, but because of the latter it has troubles extracting it's full potential through the tighter corners.

I'm not saying "this" car is better "than" that car, I'm merely pointing out that I'd wait for a set of performance figures before coming to any conclusions.

Anyhow, as for the ZR-1:

Definitely an exciting car. Interesting set of styling ques too; it really does seem to hark back to the C4 ZR-1 and that's obviously perfect for the true 'Vette enthusiast. And though I love what they've done with the side-air vents and the rear spoiler, I'm must admit to being not too fond of the glass-bonnet (doesn't work too well in my humble opinion), nor the alloys. Other than that, I haven't any complaints.

It's also interesting to learn that this engine - the LS9 - is based upon on the LS3 and not the LS7. Clearly they were looking for an engine set-up more than a tad brute than the Z06 (ZR-1/Z06): take note of the redline difference - 6,600 versus 7,000 respectively; the compression ratio's - 9:1.0 veruses 11:1.0 respectively.

Impressive beast all-around. Kudos GM.

[Merc1]

Head for the fallout shelter: the beastly Corvette ZR1 is gonna wreak some havoc.


The ZR1 is the most expensive and most powerful production Corvette in history, with a price tag around 100 grand ($110,000 for the loaded 4LZ trim level) and an estimated 620 hp at 6500 rpm and 600 lb-ft of torque at 4000 rpm from its supercharged LS9 6.2-liter V-8.

It is the first factory-built Corvette to feature forced induction, and it will also be the first Corvette to top 200 mph off the showroom floor. The idea that such a Vette could exist is certifiably bonkers.

And yet here it is. Thank you, Rick Wagoner. Thank you, Bob Lutz. And thank you Corvette vehicle lead engineer Tom Wallace.

The Heart of the Beast

Spearheading the myriad mutations needed to turn a run-of-the-mill Corvette into a ZR1 is, of course, that blown hunk of aluminum residing between the front wheels. Contrary to what you might think, the LS9 isn’t based on the Z06’s 7.0-liter LS7, but rather the base Vette’s 6.2-liter LS3 (the LS3 has 76 percent carryover parts), with which it shares a 4.06-inch bore and 3.62-inch stroke. The LS7’s cylinder walls were deemed too thin to reliably handle the extra grunt of the supercharger. The LS9 has been validated to 150,000 hours, and saw no piston, rod, or crank failures in 6800 cumulative dyno hours. The hand-assembled engines come from GM’s Performance Build Center in Wixom, Michigan, and each one is hot-tested before it goes out the door.

The all-new blower is provided by Eaton, and is the sixth in its series of Roots-type superchargers. The Gen VI “Twin Vortices Series” rides between the cylinder banks, making max boost of 10.5 psi, and Chevy claims an increase in both efficiency and noise reduction over past superchargers. An air-to-liquid intercooler sits on top of the supercharger. By lowering the engine inside the car, engineers were able to avoid the tell-tale hood bulge required for most superchargers. As a result, hood height only increases an inch, although there is little space between the outside of the hood and the engine.

Other, less noticeable changes were made under the hood, too. The LS9’s heads are made of an alloy meant to handle higher temperatures, and they sit on four-layer steel gaskets rather than the two-layer ones found in the LS3. The intake ports have swirl wings, which increase the efficiency of the combustion process, but unfortunately also cramp airflow. The supercharger’s forced air, however, mitigates the airflow problem, according to Corvette engineers.

The LS9 uses a forged steel crank and pistons, and has a lower, 9.1:1 compression ratio, as compared with the 10.7:1 ratio of the LS3. The connecting rods are titanium, like the LS7’s. The LS3 and LS9 have identical valve diameters, but the blown motor gets titanium intake and sodium-filled steel exhaust valves.

The Rest of the Voodoo

As the LS9 does its work, its many, many ponies invade the transmission, where they encounter a beefed-up six-speed Tremec unit with closer ratios than the one found in the Z06. However, first gear will still be good for 60 mph, ensuring insane performance stats. A dual-plate clutch offers enough feel and modulation, according to Chevy, to make launches a snap. We expect 0-to-60 in 3.5 seconds, or better, and the quarter-mile in 11.0 seconds.

The spring rates have been softened from those of the Z06, and the ZR1 will get the second generation of Delphi’s auto-reactive magnetic shocks standard, tuned to produce a docile ride around town in a car that required a new speedometer to 220 mph. The footwear is fat; the ZR1 gets 285/30-19s up front and 335/25-20s at the rear. By comparison the Z06 uses 275/35-18 front and 325/30-19 rear setups. As Lutz puts it, “it’s wonderfully easy to drive, but once in it, Clark Kent turns into Superman.”

The Corvette uses the same Brembo carbon-ceramic brakes as the ones found on the million-dollar Bugatti Veyron supercar. Vented and cross-drilled discs measure a whopping 15.5 inches at the front and an even 15 at the back. The front calipers utilize six pistons, and the rears four. Essentially, everything was brought up to the level needed to handle the rush of power the car can create, says product design chief and vice chairman Bob Lutz.

The ZR1 will likely be 150 pounds heavier than the roughly 3200-pound Z06, despite the liberal use of carbon fiber for the hood—which has a see-through panel in the middle for an excellent view of the top of the intercooler cover—front fenders, sill extensions, front splitter, and roof. The car has eight major panels of carbon fiber compared with six made of other materials. And GM says it will be first to offer clear-coated carbon fiber exterior panels designed to last the life of the car. The chemical additive added to the clear coat costs more than $60,000 a gallon, officials say.

The weight gain was inevitable, given all the extra hardware under the hood. “It’s literally like being fired out of a slingshot in a time warp continuum,” Lutz says, but with stability enhancement to help keep the tail straight when nailing the throttle when exiting a corner.

Production starts in July, for sale in August or September. GM can build about 2000 ZR1s a year with a choice of seven colors. Each ZR1 will have a unique identifying VIN number that incorporates the sequential build number, which should please collectors.

The Vette to End All Vettes—Literally

Since its launch, the Z06 has always been “the best dollar-for-dollar sports car on the planet,” but that’s kind of like being called the “best pound-for-pound fighter” in boxing. You may be very good, but there are still bigger, stronger opponents out there who’ll knock you flat on your rear. In the case of the Ferrari 599–baiting ZR1, however, it doesn’t look like we need any qualifiers whatsoever—it’s going to rock, plain and simple.

And with the fear that high-performance vehicles like this may be legislated out of existence in the future because they can’t meet emissions standards, we plan to enjoy every minute we can, just in case.


2009 Chevrolet Corvette ZR1 - Auto Shows - Car and Driver December 2007


M

[Bruce]

Ahh, I've only now realized the ZR-1 has ceramic brakes.

A needed item for such a monster of a vehicle.