Monday, November 24, 2014

2015 Chevrolet Corvette Z06 review: Driving the fastest 'Vette ever

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Driving the 2015 Chevy Corvette Z06: Yahoo Autos
If you ever race at Road Atlanta, pack your big boy undies. As you exit the final chicane, bouncing over the blind right-hand crest with your foot firmly planted to the floor – chugging every single one of the 650 horses on tap like Jim Morrison emptying a bar of all its vodka – you arrive at the track’s notorious 12th turn. Just a small lift is all it takes, keeping the minimum speed pegged at 110 mph. The wall is feet from the edge of the track, taunting you to lift further. You see tire marks revealing the perils of wrongdoings – a vast trail of destruction. But in this car, you needn’t fret. As Harry Hogge famously said in Days of Thunder, “you can hold it.”

The
2015 Chevrolet Corvette Z06 has widely been presumed — before a single soul outside of the company has even driven it — to be one of the best machines GM has ever built. I refused to get sucked into these presumptions, but I must admit, on paper – 650 hp, 650 lb-ft of torque; 0-60 mph in 2.9 seconds and winglets that appear fresh off the C7.R Le Mans car — it does sound bloody amazing.

After spending a day in the Z06 at Road Atlanta followed by another on the Georgian country roads, I finally have my definitive answer: Yes, the Z06, which will go on sale for around $79,000 ($89,000 with the Stage 3 aero kit), is an absolute masterpiece. It’s the best Corvette I’ve ever driven, and yet it’s not without issues.

 
 
 

 
 


The dry-sump, 6.2-liter supercharged LT4 motor is sublime. Power is up 37 percent from the outgoing Z06, and the supercharger assembly is mounted within the valley between the cylinder heads, ensuring it keeps the car’s weight distribution as low as possible. That supercharger spins to 20,000 rpm – 25 percent faster than in the Corvette ZR1, thanks to smaller rotors. This also helps the torque ramp up more effectively at low revs.

Two gearboxes can transfer that torque to the rear wheels; a glorious 7-speed manual with rev-matching or a new 8-speed automatic. That auto is eight pounds lighter than the outgoing 6-speed, five percent more fuel efficient and, according to GM, eight-hundredths of a second faster than Porsche’s dual-clutch from the 911.

On occasions, the automatic is indeed fantastic, shifting with an evocative snap that appears quicker than you can blink. However, by adding just a few degrees of steering lock, that snap disappears; Chevy engineers were concerned about it breaking the rear tires loose during cornering. The problem is that unless you are driving precisely in a straight line (which is less often than you might think on a racetrack) the gearbox feels sluggish and without emotion — that inconsistency between changes is its greatest downfall. Still, it’s comfortably the best automatic gearbox GM has ever made, but the manual remains the transmission of choice.

As I explode down the back straight at Road Atlanta, the speedometer rises quickly – 120, 130, 140, 150 mph. I turn right over a crest, heading downhill into a hard braking zone, now clocking 155 mph. I’m in 5th gear surpassing 5,000 rpm. I hit the optional carbon-ceramic brakes with all my might. The car doesn’t squirm. It doesn’t produce any noticeable pitch, or roll. It’s simply glued to the road.
“Balls,” I think. Could've braked later.
 
Even in base trim, the Z06 can lap a track unlike anything in its price range. But as you creep up to the Stage 2 downforce level, then to the maximum Stage 3 configuration with the Z07 package (which also includes larger carbon ceramic-matrix brake rotors that save 23 lbs. of unsprung mass and Michelin Pilot Sport Cup 2 tires) the car transforms both in looks and in performance.

It becomes a race car. It feels analog like a race car, it’s loud like a race car and the downforce level in Stage 3 is roughly 500 lbs. greater at top speed. In fact, the Z06 produces more downforce than any car GM has ever tested – and that includes all of its competition: “We’ve tested everything you can imagine,” said chief engineer Tadge Juechter. “The Z06 outperforms them all.”

On track, you don’t question that statement. It’s incredibly competent. It makes the brilliant C7 Corvette Stingray feel like an appropriate first car for a teenage boy. It’s Ferrari fast, McLaren fast. It’d kill a Lamborghini without even batting an eyelid.

It’s also accessible. You can reach 90 percent of the car’s capability in just a handful of laps. It won’t bite you. It won’t turn all Jackie Chan on your ass if you drive like an idiot. It behaves impeccably.
 
 
 

For most amateur drivers, this would be the end of the story. At the limit of adhesion, they’d praise the car for taking such good care of them. Only this isn’t the limit. Because of the immense downforce produced, there’s a further 10 percent hiding, accessible only to seasoned track-goers capable of digging deeper than it would seem possible. And it’s here things begin to lose traction.

What could be described as a simplistic machine, one that feels analog and raw, actually isn’t. Lapping a circuit as fast as the Z06 requires more than just big tires, plenty of power and fancy splitters. An electronic limited slip differential comes standard, equipped with a hydraulically actuated clutch that infinitely varies between fully open and fully closed.
 
 It makes its decisions based on clever algorithms that factor in minute steering inputs, throttle movements and the vehicle’s speed and yaw. And the diff is in constant communication with the Magnetic Ride suspension (which in turn is adapting consistently to changes in the road surface). This then talks to the power steering to help improve feel, which reports back to the shocks and then back to the differential again.

It’s like a merry-go-round of data, and just thinking about it makes me dizzy. So, then, imagine the difficulty the engineers faced in ensuring all these assets blend together seamlessly, and more to the point, not detract from that analog demeanor a Corvette is famous for. When approaching the true limit of the car, I discovered that it's not quite there yet.

You can feel that, during a given corner, the balance is constantly shifting. It varies along with the diff, and in the vaguest of ways, you can sense it happening. It’s never quite the same every lap. And it’s this changing balance that adds discomfort to the driving experience. You lose that unflappable confidence you had when pedaling at 90 percent.

In all fairness, though, when I drove the Z06 it was still a work in progress. The day before my test a group of engineers running the car at the Nürburgring reported back with some revised shock settings. They were adopted for the first time that morning, just an hour before I got behind the wheel. By the time the car goes on sale next spring, I wouldn’t be surprised if this subtle issue has been resolved.

But why, you ask, would a Corvette need all this tech in the first place? Isn’t that what makes a ‘Vette special – it refuses to reform with the rest of industry; like the Dodge Viper, remaining wonderfully raw and communicative? No auto-only, or V-6 turbo compromise. It’s a proper Kentucky-built super car, powered by a V-8 – the way it should be.
 
It's basically Chuck Norris. Only better looking.
 
 
 
 
Nowadays people demand a rounder, more complete character in a sports car. The effort spent implementing this technology, which on the track isn't yet fully in sync, pays off big time on regular country roads. It remains a track-focused machine, and yet it’s as comfortable on the streets as its baby brother, the Stingray.
 
 Eco mode ensures the steering is effortless, and cylinder deactivation turns the V-8 into a V-4. The engine note softens, the ride is compliant and the cabin contains just enough leather to feel somewhat luxurious. That clever tech allows the Z06 to be more than just a one-trick pony.

When you put it in Sport mode (Track mode's suspension settings are simply too stiff for the street), it comes alive. It’s incredibly engaging; constantly exciting. Yes, it is stupidly fast, but it feels so good. In many ways, I enjoyed myself more on the country roads than I did on the racetrack. There, it's a damn fine merry-go-round.

So what, now, is the point of the ZR1? If a new version does indeed arrive, the Z06 will be better on track, and just as livable on the street. It’ll be cheaper, too. Just imagine what it could do with a set of Harry’s specially staggered tires.
*****
Disclosure: For this article, the writer’s transportation, meals and lodging costs were paid for by one or more subjects of the article. Yahoo does not promise to publish any stories or provide coverage to any individual or entity that paid for some or all of the costs of any of our writers to attend an event.

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