Color us not surprised. With fuel costs growing exponentially higher and the demand for full-size trucks inversely waning, General Motors announced today that it's scaling back production of large pickups and SUVs at four assembly plants.

By eliminating one production shift at its Janesville, Wisc; Oshawa, Ontario; Pontiac and Flint, Mich. plants, GM anticipates reducing annual production by nearly 88,000 full-size pickups and 50,000 SUVs.

Products affected include the Chevrolet Silverado, Avalanche, Tahoe and Suburban, GMC's Sierra, and Yukon, and all three variants of the Cadillac Escalade. Reductions will take place in Oshawa on September 8, while the remaining four plants will see cuts as early as July 14.

The results are in from the 2009 ZR1's SAE certification: the 376 cubic inch supercharged LS9 V-8 makes 638 hp and 604 lb-ft of torque.

When the car was introduced in December, we were told to expect specific output of at least 100 hp per liter, of which the engine has 6.2. These numbers certainly make good on that promise, and work out to 103 hp per liter.

Chevrolet says the engine will be the most fuel-efficient 600-plus hp car on the market, a claim we believe since the Corvette Z06 gets a respectable 24 mpg on the highway.

Check out the gallery and articles below for a reminder of this car's awesome factor.

When Chevy unveiled its new Malibu last fall, its standard four-cylinder Ecotec engine was mated only with an outdated four-speed automatic transmission. GM promised that a proper, modern automatic would soon be available with the four-banger, and it has delivered on that promise today by unveiling a six-speed automatic called the 6T40. (A different six-speed automatic, the 6T70, was offered from the start for the Malibu, but only with the optional V-6 engine.) Production on the four-cylinder/six-speed powertrain starts shortly, so Malibu LTZ models thus equipped should be in dealerships well before Memorial Day.

At a media event today at GM's headquarters at the Renaissance Center in downtown Detroit, I had an opportunity to briefly drive a Malibu LTZ equipped with the new powertrain. Launch acceleration is crisp and strong, but with only 169 hp on tap, acceleration from 30 to 60 mph is a bit slow, so I put the gearshift lever into M, for Manual mode, and used the steering wheel-mounted paddle shifters to downshift (push them forward) or upshift (pull them back). With that maneuver, there was plenty of power, and the gearbox easily held revs past 6000 rpm.

Unlike most of GM's four-cylinder engines from the past twenty years, this one actually feels and sounds refined and quiet. I was able to drive the car for only about 10 minutes on a freeway loop, but it appears to be a well-engineered piece and an effective challenger for the highly regarded four-cylinder powertrains in the Toyota Camry, Honda Accord, Nissan Altima, and Hyundai Sonata, none of which is offered with a six-speed automatic. The six-speed has gains in efficiency, too, increasing the four-cylinder Malibu's highway fuel economy from 30 mpg to 32 mpg, which beats Camry and Accord, which both are rated at 31 mpg. The six-speed automatic Malibu gets 22 mpg in the city, the same as it gets with the four-speed automatic.

The six-speed automatic initially is exclusively offered in the top-spec LTZ model, which will cost $26,545, including destination, as a 2008 model. Chevy has this powertrain exclusively this summer, but it spreads this fall to the Pontiac G6 and the Saturn Aura.

It takes only a quick scan of the Malibu Hybrid's window sticker to see its appeal. At a base price of $22,790, the Chevy undercuts the hybrid versions of the Nissan Altima and the Toyota Camry by some $3000, making it one of the least expensive hybrid vehicles in America. The Nissan and the Toyota each return an impressive 34 mpg in the EPA combined fuel economy cycle, while the Malibu manages only 27 mpg. But driving pleasure is a different story. The Japanese sedans both feel compromised in their pursuit of ultimate economy, but the Malibu Hybrid has a smooth, unobtrusive powertrain and a nicely tuned chassis. The Chevy also wins in the steering department, although its electrically assisted rack won't keep Porsche engineers awake at night. Furthermore, the Malibu's acceleration suffers due to the long gearing of its antiquated, four-speed automatic transmission. GM needs to integrate its six-speed automatic, posthaste. Overall, though, the Malibu Hybrid drives just like the four-cylinder Malibu. And that's high praise, indeed.

Just as Saturn does for its Vue and Aura hybrid models, Chevy uses a relatively basic hybrid system for the Malibu. An electric motor replaces the alternator and can modestly boost power under acceleration. It can also act as a generator. Additionally, this motor/generator restarts the engine after it shuts down at stoplights. A battery pack linked to the motor takes up minimal trunk space.

While the Malibu Hybrid offers only a 2-mpg improvement over the conventional Malibu, the system's simplicity, low cost, and passive nature are appealing. Factor in the hybrid tax incentives, and you're almost getting something for nothing.

Chevrolet's little retro wagon, the HHR, has been given the SS treatment, with a turbocharged engine and a firmed-up chassis, plus some tuner-style body modifications and interior upgrades. The resulting car may be a little hard to take seriously, but at least there's now a lot more substance beneath the HHR's candy-coated shell.

That shell, with its pleasingly rounded styling and practical wagon layout, has been netting the HHR 100,000 sales per annum, but the Cobalt mechanicals underneath mean that those buyers are unlikely to be driving enthusiasts. Now General Motors' in-house tuner crew has imbued the HHR with newfound power and poise.

The HHR SS benefits from the latest thinking at the GM Performance Division. That means turbocharging rather than supercharging for the 2.0-liter four, which also is treated to direct injection. The benefits are twofold. First, the turbocharged engine meets 2008 emissions standards that the supercharged 2.0-liter could not. (Which explains why the Cobalt SS Supercharged has disappeared from the lineup.) Second, the 2.0 turbo makes a lot more power: 260 hp versus 205 hp, and 260 lb-ft of torque versus 200 lb-ft.

To get all 260 ponies, you need to opt for the manual transmission; the engine in the automatic-equipped car is detuned to 235 hp, in deference to the four-speed automatic's fragility. For the SS, Chevrolet has shortened the manual's shift throws and moved the shifter both forward and up so it isn't such a far reach. Unfortunately, the five-speed's shift action is pretty notchy. Chevrolet quotes 0-to-60-mph times of 6.3 seconds for the manual and 7.5 for the automatic, but the gulf between them feels greater. Whereas the 235-hp car feels responsive but nothing more, the stick-shift SS is fast; the car doesn't shoot out of the hole, but its acceleration swells as if on a wave. Stay with it, and it will carry you all the way to 150 mph. The turbo's power delivery doesn't really lag, but it does build, with a faint, telltale whistle in the background. Mostly, though, what you hear is the cacophonous noise of the direct-injection engine, with some gearbox whine tossed in. You won't mistake it for a Honda VTEC engine.

When we say that the HHR SS doesn't blast away from a stop, we should qualify that statement by explaining that this is without using launch control. Yes, just like the Porsche 911 GT2, the HHR SS has a launch control mode. Switch the traction control to the competition setting, and the car is ready for launch control at any stop. Floor the throttle and the engine holds 4100 rpm, so the turbo is spooled up when you release the clutch. The result isn't a smooth launch - in fact, it feels like you're going to snap a half shaft - but it is a quick one.

Chevy also makes much of the "no-lift shift" feature in the HHR SS. The engine-management software's programming allows you to keep the accelerator planted during upshifts. The revs rise to 6200 rpm - just shy of the 6350-rpm redline - and turbo boost doesn't drop during shifts (as you can see by checking the A-pillar-mounted boost gauge). Again, this is mostly a parlor trick to impress your friends - particularly those who will thrill to the exhaust backfire that accompanies each shift.

More so than managing engine revs, a front-wheel-drive car with 260 lb-ft of torque needs to manage torque steer. Here, Chevy has done a better job than you might expect, particularly if you've driven a supercharged Cobalt SS or the HHR's closest domestic competitor, the Dodge Caliber SRT4. Chevy engineers point to the revised roll-center height, new steering knuckles, and different antiroll-bar mounting points, which they claim help exorcise the front-wheel-drive demons. When pulling out of slow, tight corners, torque steer never raised its squirmy head on dry pavement. We also took a turn in the 235-hp car in the rain, during which we did feel tugging at the wheel, but the car didn't dart off in all directions. In all, it was a commendable performance.

In fact, the chassis tuning overall is very well done. The HHR SS gets firmer springs, dampers, and antiroll bars, which keep body lean in check. The 225/45R-18 Michelin Pilots really hang on, and the recalibrated and quickened electric power steering does a convincing impression of a hydraulic system. We'd only wish for a bit more rebound damping, as cresting a sudden rise causes the HHR SS to momentarily lose its composure. In the spring, Chevrolet will offer a further chassis upgrade in the form of Brembo front brakes with larger rotors packaged with a limited-slip differential.

The mechanical enhancements to the HHR SS have been successful, but we're not totally down with the cosmetic changes. We like the eighteen-inch wheels, but the new fascia gives the car a nose-heavy, front-wheel-drive look, and the flared lower body cladding seems out of place and is annoying to step over. Inside, there are nice, suede-like inserts on the seats, but only the driver gets the more supportive, sport bucket seat (the non-matching, standard-style passenger seat preserves the fold-flat function). There's also the aforementioned boost gauge and a smaller-diameter steering wheel.

The HHR might seem to be an odd car to get hot-rodded, but the work is certainly well done. This pint-size son of yesteryear's Suburban can now take you into the past faster than ever before.

Got Boost?

Turbocharging has replaced supercharging as the preferred horsepower helper for GM's Ecotec four. The direct-injected, 2.0-liter turbo debuted in the Pontiac Solstice GXP (followed by the Saturn Sky Red Line). There are lots more cars to come:

NOW
HHR SS

APRIL
Cobalt SS
Turbocharged coupe

JUNE
HHR SS Panel

FALL
Cobalt SS Turbocharged sedan

Like Lincoln at Gettysburg, General Motors chairman Rick Wagoner uttered but a few select words to inspire a whole new Chevrolet Corvette. Reacting to plans for the $65,800 Z06 outlined by chief engineer Tadge Juechter no score and three years ago, Wagoner mused, "I wonder what this team could do for $100,000?"

The answer is the 2009 Corvette ZR1, engineered to be the most powerful, best performing, highest priced Chevy in history. While the figures remain in flux since this blog star is still nine months from fruition, count on more than 600 hp, a top speed of more than 200 mph, 0-to-60-mph acceleration well below four seconds, and a sticker price that easily tops Wagoner's six-figure vision.

The irony is that, while the ZR1 remains loyal to tried-and-true pushrod technology, its name recalls the Corvette's brief dalliance with overhead camshafts. For six seasons, starting in 1990, Chevy teamed with Lotus to power the era's top Vette with a 32-valve, 5.7-liter V-8 that delivered 375 hp initially and 405 hp at the end of a 6939-car production run (see sidebar).

That was then, and the ZR1 is now what Juechter characterizes as, "the king of the hill, with the best of everything, in contrast to our lean and dedicated Z06 track machine. We kept changing the name to try to fool you guys as to what this new Corvette would really be called. The Blue Devil code kept the program under the corporate radar while we awaited approval.

"After debating half a dozen potential names, we decided to revive the ZR1 badge, because it fits best. Like the previous edition, this is the Corvette for our most enthusiastic customers who want top performance and the best of everything to go with it."

THE ENGINE

The star of the underhood team is a Roots-type supercharger manufactured by the Eaton Corpora-tion. Carmakers have used the supercharging gambit for more than a century because it works: when you blow more air into an engine, more power comes out.

According to Juechter, a belt-driven blower wasn't the only power booster considered. "We crammed a turbocharged car together to investigate that alternative. While it successfully demonstrated that our existing architecture could handle more power, the test car burned to the ground at Milford , ending the turbo program before I got to drive the mule."

According to assistant chief engineer Ron Meegan, who's responsible for the Corvette ZR1's new LS9 V-8, the Eaton supercharger is a sixth-generation design that debuts here. One turn of the blower's driveshaft delivers 2.3 liters of air under pressure. Configuring each of the two rotors with four lobes and twisting the lobes 160 degrees over their length boosts thermal efficiency more than 70 percent. Efficiency is important, because it determines the power required to spin the blower, the intake charge's temperature rise, and the amount of noise and vibration generated.

To avoid the top-fuel-dragster look associated with supercharged V-8s, the blower is mounted low in the engine's valley. Air enters the front of the blower, is compressed to a maximum of 10.5 psi, and is then exhausted to the intercooler positioned directly above the supercharger. Nearly a gallon of antifreeze - circulating between two heat exchangers packaged inside the intercooler housing and a third located ahead of the radiator - helps lower the charge air temperature by up to 100 degrees Fahrenheit. The belt that spins the supercharger 2.3 times crankshaft speed is a husky, eleven-rib design that also powers the water and power-steering pumps.

What lies beneath the blower is the healthiest, hardiest small-block ever. While the basic 6.2-liter cylinder case is shared with trucks and the LS3 Corvette, it's stuffed and covered with premium everything: steel (instead of sintered metal) main bearing caps, a forged-steel crankshaft, 9.1:1 forged-aluminum pistons, titanium connecting rods, a dry-sump lubrication system, and special "roto-cast" cylinder heads. According to Meegan, rotating the molds during the casting process yields a more consistent material density, thereby boosting the aluminum cylinder heads' high-temperature strength.

The heads are retained by bolts increased from eleven to twelve millimeters in diameter and sealed by new four-layer head gaskets. To save reciprocating weight, the intake valves are titanium and the exhaust valves have hollow stems. Oil jets aimed at the bottom sides of the pistons help reduce their temperature under duress. The entire exhaust system - including the hydroformed headers, catalysts, three-inch pipes, and muffler bypass valves - is an LS7 (Z06) hand-me-down.

In the interest of longevity, the LS9's flywheel is attached to the crankshaft by nine instead of the usual six cap screws. A dual-mode fuel-delivery system feeds the injectors at 36 psi during low speeds and at 87 psi when the driver indulges the throttle. While peak power and torque figures are yet to be determined, the LS9's redline has been set at 6500 rpm.

THE TRANSMISSION

The Mexican-made Tremec TR6060 transmission, overhauled for 2008 with lighter, quicker shifting, is back for another stint with fresh upgrades. The spread between first and sixth gears has been tightened by 36 percent in the interest of vitality. Armed with a 3.42:1 final-drive ratio (same as in the Z06), the ZR1 bolts to well over 60 mph in first gear. Top speed moves from fifth in the Z06 to sixth with the ZR1's closer gear ratios and lower redline. One downside is that this will be the first Corvette stricken by a gas-guzzler tax.

To provide a 50 percent increase in torque capacity with no nasty side effects, the ZR1 has been blessed with a dual-disc clutch assembly. According to transmission expert Bob Puri, the new clutch has significantly less rotating inertia, a boon to shift quality.

THE CHASSIS

Considering the dynamic strides achieved with the Z06, you might expect Corvette engineers to rest on their chassis laurels. You would be mistaken. While the hydroformed-aluminum spaceframe, rack-and-pinion steering, and core suspension components are for the most part carryover, the brakes, dampers, antiroll bars, wheels, and tires have all been upgraded for the ZR1's mission.

A practical rule of thumb is that braking capacity must rise in step with acceleration and speed potential. In accord with this non-Newtonian law, the ZR1 is upgraded with the Corvette's first carbon-composite brake system. The Brembo-supplied stoppers are described by Juechter as among "the largest carbon-ceramic rotors available on the planet." Measuring 15.5 inches in diameter in front and 15.0 inches in diameter in back, these radially and laterally vented discs were originally designed for Ferrari's FXX and Enzo, respectively. The Brembo monobloc calipers house six pistons in front, four in back.

Goodyear and Michelin periodically face off to see who deserves the honor of manufacturing the Corvette's footwear. Michelin won this go-round, so the ZR1 is shod in Pilot Sport 2 ZP (zero-pressure, or run-flat) tires, sized 285/30YR-19 in front, 335/25YR-20 in back. Twenty-spoke spun-cast Speedline aluminum wheels will be offered with a choice of a chrome or silver-painted finish.

The ZR1 also will benefit from larger-diameter antiroll bars and second-generation MR (magneto-rheological technology) dampers, which are said to be versatile enough to cover everything from flat-out racetrack lapping to smooth-road, civilian-speed touring. Juechter reports that the hardware and the software were both significantly improved for 2008.

THE BODY AND INTERIOR

Last year's comprehensive interior upgrade should nicely appease sniffy Corvette customers who will expect near perfection for their $100,000. That said, the leather-wrapped-everything package, which costs an extra $8005 in a 2008 Corvette, won't be tossed into the ZR1 for free. Juechter cites flexibility as the reason. "We're offering a fairly basic car for the track crowd and one option package with practically everything for more typical ZR1 customers," he says. For 2009 models, the high-zoot leather will be available in an expanded color palette.

About half of the ZR1's exterior panels are shared with the Z06, and the remainder switch to carbon fiber to save weight. The hood, front fenders, roof, and rocker extensions are all made of the stiff, light material to trim fat. Key pieces - the rockers, the splitter attached to the front fascia, the roof, and the B-pillar bow - are left unpainted to wow the rubes. According to Juechter, these are the auto industry's first visible carbon-fiber panels that won't yellow and crack over time due to ultraviolet light exposure. The breakthrough is a secret elixir costing $60,000 per gallon that, when added to the clear coat, blocks the harmful rays better than Bain de Soleil.

The cherry on top is a polycarbonate window - measuring roughly seventeen by nineteen inches - in the hood that provides a partial glimpse of the beast residing within.

Ready to rumble, the ZR1 should hit the streets weighing 3400 pounds or possibly a bit less, according to Juechter. The new Corvette king tops the Z06's power-to-weight ratio by about ten percent and the $270,000 Ferrari 599GTB's ratio by twelve percent.

THE BOTTOM LINE

We predict that Juechter's next presentation to his boss will prompt the GM equivalent of hugs and high fives. The ZR1 is another great addition to the Corvette's rich performance portfolio. To filch a thought from the chairman, we can only wonder what this team would do with a $150,000 price and permission to move the engine behind the driver.

In reviving the ZR1, GM taps into a storied - but no always glorious - past.

The new ZR1 might break new ground - it's the first Corvette to sport a factory-installed blower, the first to carry a gas-guzzler tax, and the most expensive Chevy in history - but the idea of an over-the-top, factory-built Corvette isn't new. Neither is the ZR1 name, which first appeared in 1970 as a $969 option for the base Vette, consisting of a 370-hp V-8 and a few drivetrain and suspension upgrades.

The next car to bear the ZR1 badge arrived in 1990. GM tapped Lotus to develop a four-cam, aluminum-block V-8 for the fourth-generation Corvette, with the goal of 400 hp and 400 lb-ft of torque. The 375-hp engine that resulted was indeed leaps and bounds ahead of the ordinary Corvette's iron-block V-8 - then producing a mere 245 hp - but it was also forty pounds heavier and far more expensive. Making matters worse, thanks to Chevy's insistence that the iron V-8's bore spacing and displacement be preserved, the bore-to-stroke ratio suffered. Ironically, Chevy's DOHC V-8 had mutated into a long-stroke compromise that wasn't optimized for high rpm.

Regardless, customers lined up to buy the 180-plus-mph, $58,995 ZR1, even though it commanded an absurd $27,000 premium over the base Vette. (Initial demand often pushed actual transaction prices beyond $100,000.) A six-speed transmission, wider rear tires, and new body panels came along for the ride. Yet demand dropped sharply after two years, and ZR1s stacked up on dealer lots. Just over 6900 cars had been sold when production ended in 1995. As for that fancy new V-8? It went the way of the dodo, shoved aside by a redesigned version of Chevy's pushrod small-block - one that was lighter, cheaper, and more compact. Given enough time, it would eventually far surpass its DOHC cousin in output, too: the current Z06's 505-hp, 7.0-liter pushrod V-8 is proof positive that complexity isn't always the best answer.

-Sam Smith