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The ZR1, Supercar? and if so, is it the best bang for your buck?
Has Chevrolet done it? Have they made a TRUE super-car? Put your favorites aside for one second, and ask your self. Does this car belong and in the super-car club? Along side of LP640's, Carrera GT's, Zonda's, SLR's, and Enzo's? I think that the ZO6 was close to being a hyper-car but it lacked in refinement, and off the track it was a little...rough. The interior was the best either, not even close. This was all do mainly to GM trying to make the "blue collar" sports car. Which I think they did. But in a white collar world, it came up a bit short. So, after going back to the drawing board and increasing the power, making some interior and exterior refinements, the Corvette is back and wanting respect. So I ask you, do you think that the ZR1 is worthy of it? The following article is something that I pulled off of autoweek.com to help those that don't know about the ZR1. Let the debating begin, BUT lets try to stay focused on the question at hand.
Blue Streak by Mac Morrison
After four years of denials, innuendo, spy shots, "wink-wink" confirmations and strategically choreographed "surprise" appearances, Chevrolet has released details of its worst-kept secret.
The 2009 Corvette ZR1--referred to during those many months of development as Blue Devil, Sting Ray and Corvette SS--will go into production next summer at the Corvette assembly plant in Bowling Green, Kentucky, and will go on sale in fall 2008. Chevy will not complete official horsepower and torque certification until spring, but Corvette assistant chief engineer Tadge Juechter says to expect at least 100 hp per liter. That equals 620 hp to go along with approximately 600 lb-ft of torque from an all-new, 6.2-liter aluminum-block LS9 V8. Juechter dismissed long-standing online forum speculation that the engine--built at the GM Performance Center in Wixom, Michigan--might produce as much as 700 hp, pointing out that 100 hp per liter is about the maximum for a reliable supercharged engine fit for everyday use.
Bore is 4.06 inches, and stroke is 3.62 (as on the LS3 used in Corvette coupes and convertibles). The LS9 has a lower 9:1 compression ratio than both the LS3 and the Z06's LS7. A new forged-steel crank, steel cylinder liners, titanium connecting rods and intake valves and sodium-filled hollow exhaust valves are all LS7 features, too, but these actual parts are unique to LS9. Twelve-millimeter head bolts (versus 10 millimeters for the LS7) and piston-cooling oil squirters are LS9-only. Pistons are forged aluminum, whereas the LS7's are cast. Valve lift remains 14 millimeters, but overlap decreases slightly in the name of refinement.
"This is not 'Z06-plus'; it's a different kind of car," Juechter said. "Z06 is kind of a lean track machine; this offers all of the performance but also everything else. It's very sophisticated and not purely for track use. It will post faster times at any track than the Z06 will, but it's also a lot more comfortable. It's for the guy who wants it all."
An Eaton Roots-type supercharger breaks new ground. The sixth-generation twin-rotor design uses four lobes on each rotor (versus three on the previous generation) and also twists each lobe 160 degrees (versus 60 degrees). The net effect is a far more efficient blower that requires less power to turn, takes up less space under the hood and weighs less. Spinning at the same speed, the new unit produces 20 percent more airflow with about 35 percent less parasitic drag on the engine. Another benefit is a reduction in induction/supercharger noise.
Rather than using a typical single heat exchanger/intercooler setup mounted directly above the engine's centerline, LS9 uses two outboard-mounted heat exchangers and intercoolers--packaging that eliminates the need for an enormous hood bulge.
With the engine mounted slightly lower than in other Corvettes and the intercoolers' location, the hood bulge is only about an inch high and should not interfere with forward sight-lines. A polycarbonate window exposes the top of the cast-aluminum intercooler cover.
Overall styling does not depart radically from that of the Z06, but several obvious visual cues differentiate the ZR1. The supercharger alone adds about 100 pounds to the car's nose, so engineers offset that somewhat with a carbon-fiber hood and front fenders that feature dual-gill air outlets behind the front wheels. The rear spoiler is new, designed to balance downforce produced by a large front splitter.
Loads of unpainted carbon fiber distinguish the ZR1, including the splitter, roof and its supporting "bow," and rocker-panel extensions. Because ultraviolet light degrades unpainted carbon fiber, General Motors bought a $60,000-per-gallon UV-blocking clear-coat additive that's used in the circuit-board industry. Juechter said carbon-fiber breakdown would have been unacceptable in a car that almost certainly will sell for $100,000 to $125,000.
Chevy skipped the carbon treatment on the rear end, partly because of weight distribution. While the Z06 comes in at 50/50 distribution, the ZR1 is in tune with the base car's slightly more front-heavy 52/48, making traction a concern. Curb weight should be about 3350 pounds, depending on equipment, roughly 200 pounds heavier than the Z06.
Larger wheels and tires also aid traction and differentiate the ZR1 from its brethren. Custom Michelin Pilot Sport 2 run-flats measure 285/30R-19 in front and ride on 10-inch-wide, one-piece Speedline 20-spoke rims; rears measure 335/25R-20 on 12-inch-wide Speedlines. The bigger wheel-and-tire combination weighs more than the Z06's, but total unsprung weight decreases, thanks to the standard carbon-ceramic Brembo brake system. Monoblock six-piston front calipers stop ridiculously large 15.5-inch front rotors, developed originally as front brakes for Ferrari's FXX multi-millionaire track-day special. Rear calipers use four pistons to clamp 15-inch rotors lifted from the Ferrari Enzo's front brakes. Stopping power should be incomprehensible, as the Brembo setup offers twice as much pad/rotor contact area as the Z06's to go along with the typical benefits of carbon-ceramic discs.
As Juechter said, Chevy wants the car to appeal beyond the ultra-hard-core set. Standard magnetic selective ride control, which offers both touring and sport modes, is a key fundamental difference from the Z06. The adjustable suspension allows for reduced spring rates and a more coddling ride, with larger antiroll bars providing enough stiffness to produce racetrack-appropriate handling in sport mode. Corvette's familiar four-mode traction/stability system remains.
Other hardware changes include steering with a mechanically variable ratio, from 17.1:1 on-center to 14.6:1 as you wind on lock. Compared with the Z06's 2.78 turns lock-to-lock, only 2.54 turns are needed. A new 260-millimeter twin-plate clutch handles the engine's torque, as do stronger prop-shaft couplings, driveshafts, ring and pinion and billet-machined steel limited-slip differential housing. The Tremec six-speed manual gearbox is strengthened internally and is a much closer-ratio box than usual for Corvettes. A tall gear allows for speeds higher than 65 mph in first, while top speed is achieved in a relatively short sixth gear rather than fifth, as is the Corvette norm. Chevy has not released performance numbers, but 0-to-60 mph should be less than 3.5 seconds--if you can put the power down efficiently. Expect a quarter-mile time in the low-11-second range, with a top speed between 200 and 205 mph, although 214 mph is theoretically possible, according to Juechter.
GM plans to build ZR1s at a max volume of approximately 2000 per year for the remainder of the C6's life cycle--about four more years--plenty of time for it to stake its claim as the all-time Corvette king.