IEEE Spectrum April, 2008 - 21

2009
cheVroLet
corVette Zr1

production cAr

n Power Plant: 462-kw

(620 hp) supercharged 6.2-L aluminum V8 n transmission: close-ratio 6-speed manual; dual clutch n Claimed Fuel
eFFiCienCy: information not available n Claimed Co2 emissions: information not available n more: chevrolet is very proud of the fact that the
Zr1's power-to-weight ratio is better than that of the Ferrari 599, the Lamborghini Lp640, and the porsche 911 gt2.

Ferrari perFormance
at one-third the price
In some ways, it's the antithesis of advanced sports-car design.
It's got an engine up front, with only two valves per cylinder,
and those valves are opened and closed with pushrods, just as
they were in engines a lifetime ago. Parts of the body are made
of fiberglass, a distinctly old-fashioned material compared
with the aluminum, magnesium, and carbon fiber used by the
Corvette's competitors.
And yet, the Chevrolet Corvette ZR1 does one thing very
well: it carries two people as fast as possible, whether on
straight or winding roads. The Corvette is the only U.S. volume
car with ceramic brake rotors and a polycarbonate window in its
hood that gives a peek at the intercooler. Chevrolet's goals are
simple: maximize power, minimize mass.
Developed under the code name Blue Devil, the ZR1 is built
around a 6.2-liter aluminum V8 developing 462 kilowatts
(620 horsepower) of power and 807 newton meters
(595 foot-pounds) of torque. The aluminum block has the
dimensions of the classic Chevrolet small-block V8, but this
one is hand-built at a special engine shop with processes used
only for racing engines. For instance, a deck plate is installed
on the aluminum block, to simulate the pressure and minute
dimensional differences created by the cylinder heads, before
the cast-iron cylinder liners are pressed into it.
A Roots-type supercharger crams air into the engine
via an intercooler, providing a denser dose of oxygen that's
nevertheless cooled down enough to fend off power-sapping
premature combustion. Like most supercharged engines, it can
deliver close to peak power over a wide range of engine speeds,
from about 2500 revolutions per minute to 6600 rpm.
28

nA * ieee Spectrum * April 2008

To handle all that power, the clutch uses a pair of smaller
discs rather than the single plate of other Corvettes. This
spreads the torque over a greater area and reduces inertia by
25 percent, letting the engine spool up or down more quickly.
As with the highest-performance German cars, the ZR1's brake
rotors are made of ceramic silicon carbide reinforced with
carbon fiber, which is less susceptible to the friction-induced
changes that can cause brake power to fade temporarily after
repeated high-speed braking.
Ride control on the ZR1 employs a suspension of
magnetic particles in a fluid instead of mechanical shocks.
The viscosity of the fluid changes in response to a magnetic
field, which varies every millisecond in response to inputs
from sensors providing data on speed, suspension, and road
surface conditions.
The roof, hood, front fenders, rocker panels, and some
smaller parts are made of carbon fiber instead of steel, and the
weight saved offsets the heavier engine. The car weighs just
1520 kilograms (3351 pounds).
Chevrolet hadn't released performance data by press
time, but it said the ZR1 is expected to be the first production Corvette to exceed 320 kilometers per hour (200 miles per
hour). It's rumored that the car accelerates from 0 to 100 km/h
(62 mph) in less than 3.5 seconds. The factory did confirm that
the cornering grip is more than 1 g-enough to make you feel
twice your weight in a perfectly banked curve. That's among
the highest g-forces of any production vehicle today.
At roughly US $100 000, the ZR1 bests cars costing two to
four times as much. It's the only U.S. vehicle that routinely
competes successfully in the fabled 24 Heures du Mans race,
better known as Le Mans-heady company indeed for a car
from Kentucky. o
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Table of Contents for the Digital Edition of IEEE Spectrum April, 2008