For the nearly 55 years that Chevrolet has been building the Corvette, it has stood out as an American icon: a sports car that can compete with high-priced imports at a fraction of their cost. Throughout their history, Corvette coupes and roadsters have pushed the limits of automotive technology and innovation. The Corvette was one of the first production cars to use a lightweight fiberglass body and four-wheel disc brakes. There are six generations of the Corvette, and each one has meant a leap forward in exterior design and performance technology. But with the 2009 Corvette ZR1, which is set to go on sale in fall 2008, the Corvette may have made its biggest jump yet. The ZR1 has been developed not just to compete with other sports cars, but to take on supercars made by Ferrari, Lamborghini and Porsche.
The ZR1 is joining an impressive family. The sixth-generation Corvette, or C6, is currently on the market, and the base model produces 430 horsepower and 400 foot-pounds of torque. The C6 is also available as a Z06 performance model, which generates 505 horsepower and 470 foot-pounds of torque. While those are impressive numbers, the ZR1 needs to do even better to lure buyers out of import dealerships.
So, the question isn't just how well the ZR1 will stack up against the best that Italy and Germany have to offer, but how it's going to lure buyers away from those cars. General Motors, Chevrolet's parent company, is betting that the technology under the ZR1's hood -- as well as what's under its paint -- will generate enough raw power to overcome import prestige. Keep reading to learn how the Ferrari-chasing technology in the 2009 Chevrolet Corvette ZR1 works.
ZR1 Development and Supercharger
The development of the ZR1 started when General Motors CEO Rick Wagoner looked at the $60,000 Corvette Z06 and wondered what the Corvette team could develop if it was shooting for a $100,000 'Vette. The result was a secret GM project labeled "Blue Devil" (after Wagoner's college mascot at Duke University) that took four years to become the most expensive Chevrolet ever built.
Along the way, the development team tested the bounds of automotive technology. An experiment with a turbocharged engine showed promise -- until the test car burned to the ground at GM's test track. Still, the team pushed on and created a car that is expected to appeal to the kind of buyers who normally shop at high-end Italian car dealerships. Corvette Vehicle Line Executive Tom Wallace got more specific, telling Motor Trend magazine that he expected the ZR1 to compete with the Ferrari 599, Lamborghini Murciélago and "any Porsche" [source: Motor Trend]. Keep reading to learn what the ZR1 has that allows it to compete with the best cars in the world.
What puts the ZR1 on the same playing field as other supercars is the engine's power. When the turbocharging experiments failed, the Corvette team turned to supercharging. A supercharger, also called a blower, is a device that shoots compressed air into an engine by forcing it through rotating chambers. The more air an engine has, the more power it creates. A belt on the engine turns the supercharger, allowing it to suck outside air into the engine. The ZR1 uses a Roots-type supercharger, which has four lobes that lock together like gears. Most superchargers have only three lobes. The lobes on the ZR1's supercharger also rotate 160 degrees -- lobes in most superchargers rotate only 60 degrees. The four-lobe design and extra rotation increases thermal efficiency and has nearly the same power efficiency as a turbocharger. With every rotation, the ZR1's blower forces 2.3 liters of pressurized air into the engine. To avoid the massive bulge on the hood that's usually associated with superchargers, the ZR1's blower is mounted low in the V of the V8 engine and uses side-mounted intercoolers and heat exchangers.
ZR1 Engine and Transmission
Though the supercharger on the ZR1 is one of its standout characteristics, its LS9 engine is no slouch, either. The engine shares its basic 6.2-liter design with other Corvettes but features some extra high-end materials and parts that are lighter and stronger than conventional engine parts -- like a forged steel crankshaft, steel main bearing caps, titanium connecting rods, forged aluminum pistons and roto-cast cylinder heads that have a more consistent density than other heads. There's more titanium on the intake valves (to save weight without losing strength), and the stems on the exhaust valves are hollow. Even the engine's flywheel has been modified for supercar duty. The flywheel on base and Z06 Corvettes is attached to the crankshaft with six screws, while the ZR1's is attached with nine.
Sending the engine's power to the wheels is a six-speed Tremec TR6060 transmission with a close-ratio gear set. On the ZR1, the gearing is 16 percent longer than that of the Corvette Z06, which means the ZR1 can get to over 60 mph without leaving first gear. For higher gears, the spread on the ZR1 is 26 percent shorter than the Z06. Though this makes for a lower redline in fifth and sixth, it also means the ZR1 easily scoots to over 200 mph. To further handle the engine's torque output, the gear, shaft gear and shaft materials were strengthened, and a twin-plate clutch was used to improve shift feel.
The ZR1's chassis is similar to the Corvette Z06. It uses the same aluminum structure but has some carbon fiber components to offset the engine's extra weight (hey, superchargers can be heavy). The ZR1 also has GM's Magnetic Selective Ride Control System, which allows drivers to select the type of suspension responses they prefer. On the ZR1, the system uses Magneto-Rheologial shocks, which adjust automatically based on driving conditions for optimal ride and control. The ZR1 also has stiffened and larger anti-roll bars. All together, the suspension system is designed to make the ZR1 a comfortable road car that can provide blistering track times.
Of course, a car like the ZR1 needs maximum stopping power. Its front brakes are 15.5-inch carbon-ceramic rotors, and the back rotors are 15 inches. Both are radially and laterally vented discs (to avoid too much heat) and were originally designed for the Ferrari FXX and Enzo. The calipers are Brembo monoblocs with six pistons in front and four in the back.
Connecting the ZR1 to the road are larger tires than on other Corvettes. The ZR1 has Custom Michelin Pilot Sport 2 run-flat tires on the front. They sit on 10-inch, one-piece 20-spoke rims from Speedline and measure 285/30R-19. In the rear, the tires measure 335/25R-20 and sit on 12-inch Speedlines.
ZR1 Style and Performance
The ZR1 takes most of its styling cues from the rest of the C6 line, but to reduce weight, GM used a number of carbon-fiber panels. The fenders, hood, chin-spoiler, rocker panels and roof are all made of the lightweight but strong material, and some of the pieces have been left unpainted, so you can actually see the carbon fiber, which is an industry first. Usually, carbon-fiber yellows and cracks when exposed to ultraviolet light, but Chevrolet uses a special coating (that reportedly costs $60,000 a gallon) to protect the carbon-fiber on the ZR1.
The ZR1 also has a few specialized exterior flourishes. The more powerful braking system requires front and back brake vents that are larger than on other Corvettes. The brake vents aren't all about utility, though: The front vents feature horizontal gills, in an homage to the 1963 Corvette. The ZR1's hood also has a slight bulge in it (to contain the engine), which features a window that looks down on the engine. An air intake at the front of the hood helps bring air into the engine, and a larger chin spoiler helps the ZR1's nose stay planted. A full-width spoiler does the same for the rear.
For a $100,000 car, the ZR1's interior can be surprisingly basic. That's because Chevrolet wanted to appeal to buyers looking for a stripped-down track car, as well as those looking for luxury. While the interior design isn't changed much from a base Corvette's, the ZR1 has a boost gauge and ZR1 logos on the headrests and tachometers. A leather-wrapped interior is available.
With all of that hardware, it's not surprising that the ZR1 can produce some truly amazing numbers.
- The ZR1's 6.2-liter V8 produces 100 horsepower per liter. That's right: 620 horsepower is standard, along with 600 foot-pounds of torque.
- The ZR1's top speed hasn't been released yet, but GM expects it to top 200 mph.
- The zero-to-60 time is expected to be less than 3.5 seconds, with a quarter-mile time in the low 11 seconds.
- The ZR1 weighs about 200 pounds more than the Corvette Z06, but with all the extra power, the extra weight shouldn't be a problem. Even with its 3350 curb weight, the ZR1's power-to-weight ratio is 10 percent better than the Z06's and 12 percent better than the Ferrari 599 GTB's.
Of course, there are some downsides to the ZR1's performance -- not that anyone with $100,000 to spend on a car will notice. The ZR1 is the first Corvette to be subject to the gas-guzzler tax, even though the EPA hasn't released its estimated fuel economy for the car. Car and Driver magazine estimates to fuel economy to be 14 mpg in city driving and 23 mpg on the highway [source: Car and Driver]. Premium fuel is required, but that's a small price to pay for premium performance.
General Motors is hoping to position the ZR1 as a bargain alternative to other supercars. The ZR1 should compete with the Porsche 911 GT2, Ferrari 599 GTB and the Lamborghini Murciélago. While no head-to-head comparisons have been done, the ZR1 appears to be an able challenger.
- The Ferrari 599 generates roughly 600 horsepower and foot-pounds of torque like the ZR1 but needs a V12 engine to do it. The Ferrari 599 also takes 3.7 seconds to get to 60.
- The Porsche 911 GT2 produces 530 horsepower and 505 foot-pounds of torque, and can get to 60 in 3.6 seconds.
- The Lamborghini Murciélago, like the Ferrari, uses a V12 engine to produce 572 horsepower and 479 foot-pounds of torque. It has a 3.8 second zero-to-60 time.
On paper, it looks like GM's bet may pay off: The ZR1 can hold its own, at about half the price of other supercars.
To learn more about the Corvette and other sports cars, take a look at the links on the next page.
Related HowStuffWorks Articles
More Great Links
- Bailey, Shaun. "2009 Corvette ZR1: Unveiling the Super Vette." Road and Track. February 2008. http://www.roadandtrack.com/article.asp?section_id=7&article_id=6298
- Corvette ZR1. http://www.chevrolet.com/corvette/zr1/
- GM Media Online. http://media.gm.com/us/gm/en/news/events/autoshows/08naias/brands/chevrolet/index.html
- Markus, Frank. "The Devil's Own." Motor Trend. February 2008. http://www.motortrend.com/roadtests/coupes/112_0802_2009_chevrolet_corvette_zr1_first_look
- Morrison, Mac. "Blue Streak." Autoweek. Dec. 24, 2007. http://autoweek.com/apps/pbcs.dll/article?AID=/20071220/FREE/735513721
- Swan, Tony. "Blown Away." Car and Driver. February 2008. http://www.caranddriver.com/previews/14458/2009-chevrolet-corvette-zr1.html
- Sherman, Don. "The Mother of All Vettes." Automobile Magazine. February 2008.