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Mechanics August
Engine
Viper's 8.0-liter engine is the
largest and most powerful available today in an American production sports
car. Viper GTS Coupe and RT/10 Roadster share the same 450 horsepower (460
in GT2 and ACR models) engine, suspension, brake system and adjustable
pedal set.
Air intake is through a cast aluminum manifold with
formed tubes, including an integral fuel rail cored in the castings. The
dual throttle bodies and bottom-feed high-impedence fuel injectors control
fuel flow and mixture. Fuel is fed to the injectors by a sequential
multipoint injection system.
The engine's forged aluminum pistons
are set in cast iron liners. The aluminum cylinder head features a
conventional two valves per cylinder with higher-revving dual valve
springs.
While a natural extension of the classic American V-8 (the
small-block LA series, to be exact), a number of the V-10's unusual design
features were derived from Formula One engines. Among these features are a
closed tappet gallery for better intake manifold seating, and a
sophisticated internal water flow system which traces its route outside
the engine block, inside the cylinder head, around each cylinder and
inside each combustion chamber for increased engine cooling.
Spent
combustion gasses travel through a stainless steel tubular exhaust
manifold, then pass through unique sill-mounted catalytic converters and
exit at the center rear.
The six-speed manual transmission was
designed to harness Viper's substantial power and match its
high-performance expectations. It boasts an electronic reverse lockout
feature and first-to-fourth skip-shift for fuel economy.
In
developing this engine, Team Viper set out to maintain the simple
powertrain design of classic high-performance sports cars -- because
simplicity leads to durability, reliability and
serviceability.
Chassis Construction
Viper's massive V-10 engine
is mounted on what is believed to be the stiffest sports car chassis ever
built.
The engine is cradled by two massive rectangular-tube frame
rails, which turn out at the front bulkhead and continue on down the
sides. Positioned between the front bulkhead and the back of the cockpit
is a central backbone of smaller rectangular tubes. This is attached at
the back to a cage or box which encompasses the rear suspension, a
19-gallon fuel tank, a spare tire, the battery and the trunk.
The
fully independent front and rear suspensions feature unequal-length upper
and lower "A" arms and coil-over springs made of lightweight, yet strong
micro-grain alloy steel. High-performance gas-filled shocks minimize
aeration.
The power-assisted rack-and-pinion steering system
features positive on-center feel and a fast 16.7:1 steering ratio for
quick and responsive maneuvering. Lock to lock is accomplished in a mere
2.4 turns. Viper's turning circle is 40.5 feet and its maximum turning
angle is 28 degrees.
Viper's high performance brake system features
four-piston front calipers with huge 13" x 1.26" vented rotors up front
and 13" x.86 vented rotors at the rear. This system was specially designed
to help meet the stated test-track goal of 0-100-0 mph in less than 15
seconds.
Truly massive high performance Michelin Pilot Sport tires
created for the Viper are instrumental in translating the car's abundant
horsepower and torque to more linear terms. These directional tires,
275/35ZR18 front and 335/30ZR18 rear, are a major factor in Viper's 1g
lateral acceleration capability.
The tires are mounted on forged
aluminum wheels with Viper logo centers (BBS forged aluminum wheels with
chrome Viper Head center caps for the GT2 and ACR models).
Finally,
Viper's cooling system consists of a lightweight copper-core radiator and
an electronically controlled dual-speed electric fan. A front-mounted
engine air-to-oil cooler is also standard.
Assembly And
Testing
Each Dodge Viper is hand-assembled at a special Detroit,
Michigan facility on Conner Avenue by carefully chosen, skilled UAW
workers with over 300 hours of training each.
Each Viper is made up
of approximately 50 component modules which are shipped to the Viper
facility from locations throughout North America. Stamping, casting,
painting and welding take place off-site. Composite body panels arrive
already painted. Complete instrument panels are supplied with the gauges
tested and set in place. Engines are assembled and tested at a Chrysler
engine plant.
The Conner Avenue Assembly Plant has adjacent work
stations. Adjustments are made at each work station by individual
craftspersons acting as their own inspectors, eliminating traditional
repair stations and inspectors. Problems are immediately dealt with, even
if they require a discussion with the on-site Team Viper engineer. All
procedures are verified by assembly team members, with working team
leaders coordinating efforts through craft managers.
The Viper
assembly process is as unique as the car itself, even extending to testing
procedures. For example, as is the case with race cars, wheel alignment
includes adjustment of "bump steer." A special machine is used to align
all four wheels off their wheel hubs. In this way, the wheels are moved up
and down in their suspension travel and alignment is set in three
different positions.
Every Viper is also "roll tested," which
involves running the car at speed, in place, on special rollers right at
the assembly center while the car is a "hot rolling chassis" minus all
body panels. It is driven through all six speeds of its transmissions, up
to 90 mph, in order to validate the proper functioning of all systems
under actual driving conditions.
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