Chevrolet Corvette ZR1 Features Supercharged LS9 Engine
The
supercharged LS9 6.2L small-block engine is the power behind the ZR1's
performance. A sixth-generation Eaton supercharger helps the LS9 make big power
and torque at lower rpm and carries it in a wide arc to 6,600 rpm, as it pushes
enough air to help the engine maintain power through the upper levels of the rpm
band - the area where supercharged performance tends to diminish. Heavy-duty and
lightweight reciprocating components enable the engine's confident high-rpm
performance.
The Roots-type supercharger uses a unique, four-lobe rotor
design. It is augmented with an integrated charge cooling system that reduces
inlet air temperature for maximum performance.
The LS9 is hand-assembled
at GM's Performance Build Center in Wixom, Mich., and incorporates special
processes typically seen in racing engines to produce a highly refined and
precise product. For example, cast iron cylinder liners are inserted in the
aluminum block and are finish-bored and honed with a deck plate installed. The
deck plate simulates the pressure and minute dimensional variances applied to
the block when the cylinder heads are installed. This ensures a higher degree of
accuracy that promotes maximum cylinder head sealing, piston ring fit and
overall engine performance.
Transmission and Axle
The LS9
engine is backed by an upgraded, stronger six-speed manual transmission and a
twin-disc clutch that provide exceptional clamping power, while maintaining an
easy clutch pedal effort. ZR1-specific gearing in the transmission provides a
steep first-gear ratio that helps launch the car, and top speed is achieved in
sixth gear.
The twin-disc clutch system employs a pair of discs, which
spread out the engine's torque load over a wider area. This enables tremendous
clamping power when the clutch is engaged, while also helping to dissipate heat
better and extend the life of the clutch.
The twin-disc clutch system
also contributes to the ZR1's exceptional driving quality, with smooth and easy
shifting. The twin-disc system's design allows higher torque capacity with
inertia and pedal effort similar to the Chevrolet Corvette Z06. It enables a
25-percent reduction in inertia, thanks to smaller, 260-mm plates; the Chevrolet
Corvette Z06's uses a 290-mm single-disc system.
The rear axle also is
stronger in the Corvette ZR1 and features asymmetrical axle-shaft diameters - 33
mm on the right side and 40 mm on the left - that were developed after careful
testing to provide optimal torque management. The axles are mounted on a more
horizontal plane that correlates with the wider width of the rear wheels and
tires.
Performance Traction Management
Performance Traction
Management (PTM) technology is an advanced system that is part of the ZR1's
Launch Control feature, which optimizes traction for greater and more consistent
on-track performance.
The PTM system holds a predetermined engine speed
while the driver pushes the throttle to the floor. That allows the driver to
quickly release the clutch and the system modulates engine torque 100 times per
second to maximize the available traction. The system is capable of approaching
a skilled driver's best effort and repeats it consistently.
PTM also
integrates the ZR1's traction control, active handling and selective ride
control systems to enhance race track driving consistency and overall
performance. When full throttle is applied upon exiting a corner, it
automatically manages acceleration dynamics.
Ride and Handling
The Corvette ZR1 is built on the same aluminum-intensive chassis as the
Corvette Z06 and features similar independent SLA front and rear suspensions,
with aluminum upper and lower control arms. Where the ZR1 differs is the
suspension tuning, which was optimized for the car's steamroller-wide front and
rear tires.
Magnetic Selective Ride Control is standard and tuned
specifically for the Corvette ZR1. The system's ability to deliver a compliant
ride with nearly instantaneous damping adjustments enabled engineers to develop
a surprisingly supple ride quality in a supercar that still delivers cornering
grip of more than 1g.
From a high-performance perspective, Magnetic
Selective Ride Control helps the rear axle remain planted during launch for
smooth, hop-free acceleration. It also helps suppress axle movement when
cornering on broken or uneven pavement.
Brakes, Wheels and Tires
Commensurate with the Corvette ZR1's engine output is the braking system,
headlined by Brembo carbon-ceramic brake rotors. Found on only a few exotics and
more expensive supercars, carbon-ceramic brake rotors are made of a
carbon-fiber-reinforced ceramic silicon carbide material. The advantages of
these rotors are low mass and resistance to wear and heat. In fact, the rotors
should never show corrosion or require replacement for the life of the vehicle,
when used in normal driving.
The vented and cross-drilled rotors on the
ZR1 measure 15.5 inches (394 mm) in diameter in the front and 15 inches (380 mm)
in diameter in the rear - making them among the largest carbon-ceramic rotors
available on any production vehicle.
Clamping down on the high-tech
rotors are six-piston front calipers and four-piston rear calipers, each painted
a ZR1-exclusive blue. The brakes are visible through the ZR1's exclusive wheels:
20-spoke alloy rims that measure 19 x 10 inches in diameter in the front and 20
x 12 inches in the rear. A Sterling Silver paint finish is standard; chrome and
Competition Gray versions are optional. The wheels are wrapped in Michelin Pilot
Sport 2 tires developed specifically for the ZR1, measuring 285/30 ZR19 in front
and 335/25 ZR20 in the rear.
Exclusive Exterior
The ZR1 is
instantly recognizable, with perhaps the most identifiable feature a raised,
all-carbon-fiber hood that incorporates a clear, polycarbonate window. The
window provides a view of the top of the engine's intercooler, with the legend
"LS9 SUPERCHARGED" embossed on the left and right sides, and an engine cover
with the Corvette crossed flags logo debossed at the front.
The underside
of the hood has a visible carbon-fiber-weave. Visible carbon-fiber is used on
the roof, roof bow, rocker molding and front splitter. These exterior components
are protected by a specially developed glossy, UV-resistant clear coat that
resists yellowing and wear.
Widened, carbon-fiber front fenders with
specific, dual lower ports; and a full-width, body-color rear spoiler
incorporating the center high-mounted stop lamp are also unique to the ZR1. All
of the exterior features were developed to enhance high-speed stability and
driver control.
High-Quality Materials in the Interior
The
ZR1 interior builds on the brand's dual-cockpit heritage, with high-quality
materials, craftsmanship and functionality that support the premium-quality
performance. The ZR1 cabin differs from the Corvette and Corvette Z06 with the
following:
- ZR1-logo sill plates
- ZR1-logo headrest embroidery
- Specific gauge cluster with "ZR1" logo on the tachometer and a 220-mph
(370 km/h) readout on the speedometer
- Boost gauge added to the instrument cluster and head-up display.
The standard ZR1 (RPO 1ZR) comes with accoutrements based on the Z06,
including lightweight seats and lightweight content. The uplevel interior
package (RPO 3ZR) includes power-adjustable, heated and leather-trimmed sport
seats (embroidered with the ZR1 logo); Bose premium audio system; navigation
system; Bluetooth connectivity; power telescoping steering column; custom
leather-wrapped interior available in four colors; and more.
Optional
custom interior color stitching is new for 2011.
Chevrolet Corvette ZR1: Photo Gallery, Review (1/2) and Specifications