dimanche 6 mai 2018
Chevrolet Corvette ZR1
Chevrolet Corvette ZR1The new king of ’Vettes breaks all the laws (of physics)
In “A Briefer History of Time,” the late Stephen Hawking’s layman’s version of his bestselling book, the astrophysicist quickly blows out the notion of absolute space and absolute time. It reads like theory, but after driving the 755-hp 2019 Chevy Corvette ZR1, I now know that time travel is possible. The newest ’Vette doesn’t merely get you around a racetrack, it teleports you from one corner to the next. Once there, you can carry so much speed it’s as if you’re in a rocket slingshotting around the moon to get to Mars. And as someone who, until now, only ever became nauseous in the passenger seat while on a racetrack, I can say that time travel is tough on the internal organs. The only respite is on long straights, like at Road Atlanta, where besides easily cresting 150 mph, a driver can relax, get his or her bearings back and prepare for the next 40-mph left-right combo.
For those not familiar, the new ZR1 is the fastest, quickest and most powerful production Corvette Chevrolet has ever built. Along with those 755 ponies, buyers get 715 lb-ft of torque from the new LT5: a hand-built 6.2-liter V8 with a 2.65-liter Eaton supercharger tacked on top. That supercharger is nearly a liter bigger and just under 3 inches taller than the Z06’s, which necessitates a “halo” hood. Before you ask, it’s visible from the driver’s seat but not intrusive.
The 2019 ZR1 follows in a long line of world beaters, which began in 1970. That year the “ZR1” was a hardcore track package with heavy-duty brakes, unique suspension, an upgraded transmission and an extra-large aluminum radiator. It had no power steering, radio or air conditioning. The next ZR1 came during the fourth generation, or C4, Corvette in 1990. It housed a 32-valve V8 built by Mercury Marine and made 375 hp. Later, the output was bumped to 405, not a small number in 1993. In 2009, we received the codename “Blue Devil” ZR1 making 638 hp with the LS9 small block
In 1990, the ZR1 cost about $60,000. The 2009 ZR1 cost $100,000, and we stand here today with a ZR1 that starts at $121,000, including destination. A fully optioned convertible approaches $145K.
That’s big money for a Corvette, but this car is all about eye-popping figures. It accelerates to 187 mph from standstill in 1 mile and will eventually reach 212 mph with the less aggressive wing. From that top speed, it decelerates back to zero in a gut-punching 8.7 seconds. That’s time travel. Have a passenger try to hold a clock when you do that.
It has more stick than Gorilla Glue thanks in part to near-race-slick Michelin Pilot Sport Cup 2 tires. Those come with the $2,995 ZTK package, which also adds a more aggressive rear wing, firmer springs and shocks, and removable carbon-fiber end caps for the front splitter. It’s the only available option package. To get all of the luxury accoutrements Corvette buyers enjoy, like a leather interior, heated/vented seats, premium audio, satellite radio and a microfiber-wrapped headliner, you’ll have to order the 3ZR trim for $10,000. It also comes with navigation and the Performance Data Recorder (a front-mounted camera that records your laps with data), both of which are optional on the base 1ZR trim. Keyless entry, a color head-up display, rearview camera, xenon headlights, power seats and two 8-inch color displays are standard across the board.
The ZR1 was developed on a rolling road wind tunnel that can put the coupe in both straight-line and angled (yaw) conditions that it might encounter on a racetrack. That big rear wing plays a big role in making 60 percent more downforce than the Z06 Stage 3 package, 950 pounds at top speed, in all. Other contributing parts include the the front splitter and underbody belly pan. Along with the wind tunnel, computational fluid dynamics simulations told engineers where to put all those winglets, air catchers and side vents.
Heat was obviously a concern with a motor this big, hence the giant intakes in front that allow 41 percent more airflow than the Z06. The ZR1 has 13 heat exchangers (including radiators, trans, oil and diff coolers) compared to the Z06’s nine. To prove they all work, Chevy torture-tested the car on-track at temperatures up to 100 degrees Fahrenheit. It was mild at Road Atlanta, the perfect place to test this car, but temps on the standard 15.5-inch carbon-ceramic rotors housed in front checked in near 800 degrees.
The rears discs measure a generous 15.3 inches, and the Brembo calipers are six-piston front and four-piston in the back. They’re not all the same size pistons either -- that would be too easy. The leading pistons are smaller, and the larger ones are in the back. That equals out the pressure when the brakes engage. The giant brake pads are hybrids, using both race and road friction material. And, according to Brembo, they’re good up to 1,400 degrees, making my 800-degree readout seem almost pedestrian.
The Execution
If I knew I was gonna slingshot to Mars, I would have done more than learn Road Atlanta’s legendary 12 turns and 125 feet of elevation change on "Forza Motorsport 7." I’d have enrolled in Space Camp. After 25 laps grouped in five-lap stints, my innards give up. I get out of the car, red-faced and woozy, yank my helmet off and suck in some wind. Worn out by the immense lateral grip.
From the air, Road Atlanta looks like a tomahawk, but from the ground it’s a sea of S-turns. And the ZR1 loves S-turns. The front tires are a half-inch wider than the Z06’s. That contributes to the ZR1 having such an immediate turn-in that, even in tour mode, your brain can’t get info to your inner ear fast enough. A lap goes like this: apex, apex, apex, break the sound barrier down the straight, apex, apex, apex, another sonic boom and you’re done. Seat of the pants feels like I pulled 10 lateral gs, Alas it’s less than 2. But keep in mind, astronauts only experience about 3 gs on liftoff.
The steering ratio is supercar quick. The only cars that feel quicker are the Alfa Romeo Giulia QF, the Acura NSX and maybe a McLaren or two. Changes of direction are instantaneous and, if you’re in track mode, the double wishbone suspension at all four corners allows zero body roll. That means your body does all the moving. The optional Competition Sport carbon-shelled seats are great, but you need more than that when jumping dimensions. A six-point harness and a race seat would help. I push harder on each successive lap and never slide, never go off-course. Even down the steep hill, where I drop 70 feet before turn 12: a high-g, 100-mph right onto the front straight
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