 Visually,
the second generation Viper is quite disappointing compare with its
predecessor
(especially the 1995 Viper GTS). The original Viper delivered a wild
and
uncompromising feel through its radical curvy surfaces and muscular
profile.
It was also a little retro, so from the first sight you would know,
"Wow!
this is an American muscle car". The second generation Viper has
changed
its design philosophy - curvy surfaces were straightened, muscles
disappeared
as a result. Now it just look low, wide and long. No wildness, no
imagination,
no American spirit anymore. The reason behind this change is:
Chrysler’s
design guru Tom Gale retired in year 2000, thus the design work of
Viper
was shifted to Osamu Shikado, who used to design Toyota Camry. No
joking.
However, even the Italian can’t compete with the tremendous torque generated by the 8.3-litre American V10 - at 4,200rpm, there is an astonishing 525lbft available. In the whole automotive world, only 3 engines are more torquey: Pagani’s AMG 7.3-litre V12 (553 lbft), Mercedes’ 5.5-litre twin-turbo V12 (590-664lbft depends on tuning) and Bentley’s 6.75-litre twin-turbo V8 (645 lbft).
As before, Viper uses a tubular steel backbone chassis (like TVR). Bodyshell is low-cost plastic composite molding (again, like TVR). There are some new materials however, such as the cast magnesium under-dash cross member and roof frames, and carbon fiber inner supports for fenders. Compare with the old Viper GTS, the new car is marginally shorter but wheelbase is 6cm longer. Overall weight is reduced by 36kg, making it levels with Porsche 911 Turbo. Suspensions are classic double-wishbones all round, made of aluminum. Attached to them are wide tyres and huge Brembo brakes, whose discs are 355mm large.
Nevertheless, like TVRs again, the Viper does not handle and ride like supercars. Yes, its firm suspension results in rock-steady cornering. Its heavy steering is race-car-quick and transmit good road feel. Its huge rubber generates massive grip. However, given a twisty road, the Viper suddenly feels too wide to be enjoyable. Its harsh ride and bump steer discourage you to push harder, unlike other good supercars. A Corvette Z06 is easier to drive faster, and more enjoyable to do so. The Viper, on the other hand, remains very much a muscle car in its blood.
|
| The above report was last updated on 22 Dec 2002. All Rights Reserved. |
The
development direction of the new Viper is to make it more civilized and
easier to drive. However, this is just relative to the old Viper.
Talking
about refinement is nonsense in any Viper review. This car is still
very
rough, very unrefined and uncomfortable. Its suspension is still tuned
very stiff, just like without any suspension travel. Its steering still
generates bump steer and kickback on any roads other than race tracks,
so the driver must keep his hand firmly on steering wheel. Its
heavy-duty
Tremec T56 gearbox shifts like a truck’s. Its truck-derived V10 engine
(with unbalanced 90° V-angle) cannot compete with rivals for
smoothness
and willingness. Its cockpit is full of cheap plastics, cheap switch
gears
and poor taste. 
But
you won’t buy Viper for its refinement. Wild performance is still its
selling
point, and the new Viper has enhanced its already remarkable
performance
further. The mega aluminum V10 has gained 300 more c.c. to an
astonishing
8277c.c. (or 505 cubic inches), making it once again the biggest road
car
engine in the world. With so big capacity, you won’t mind it still
relies
on push-rods to activate its 2 valves per cylinder, you won’t mind it
fails
to spin over 6,000rpm, because it pumps out a full 500 horsepower at
5600rpm,
50hp more than before. Yes, five hundred horsepower! you need some
Italian
V12s to outpower it. 
Inevitably,
there is concern whether the mega V10 will make the chassis unbalanced.
In fact, Viper achieved better balance than even Ferrari 575 Maranello
- some 52% of the kerb weight is acted on the rear wheels, perfect!
this
must thanks to the "cab-backward" design that put the whole engine
completely
behind the front axle. Also, the V10 is cast from aluminum to cut
weight,
unlike its truck origin. Besides, the new Viper also positions its
engine
some 2.5 cm lower than before in order to lower center of gravity.
Driving
the Viper is a sensation. The torque and acceleration force is
astonishing
- Motor Trend found it takes 4.1 seconds from 0-60mph and 9.5 seconds
to
100mph. Car And Driver timed even quicker. It is therefore sufficiently
quicker than the next fastest American sports car, Chevrolet Corvette
Z06.
Undoubtedly, Viper is one of the few supercars in the world - the
others
are Ferrari Enzo, Pagani Zonda C12S, Lamborghini Murcielago, Ferrari
575M,
Porsche 911 GT2 and Turbo, TVR Tuscan S and Cerbera 4.5. However,
following
the tradition of American cars, Viper is the cheapest among its rivals
bar the TVRs. 
From
engineering point of view, the Viper Coupe did not improve from the
roadster as much as the legendary GTS did. You might remember the old
car was launch as a mid-life update of the Viper, thus it brought a lot
of chassis improvement and significant increase of horsepower. In
contrast, the Viper Coupe has its entire powertrain untouched. The only
thing it improved is a slightly stiffer chassis (thanks to the fixed
roof) and slight reduction of aerodynamic drag, from 0.40 to 0.39,
though that figure is nothing to be proud of. More welcome is a bigger
rear spoiler, which generates 45 kg of downforce at 150 mph. Well,
that's not a big number, but at least better than none.
The 2008 Viper has a number of
improvements, but at the center stage is unquestionably the new
8.4-liter, 600-horsepower engine. That is 90 horsepower higher than
last year's car.
The most surprising addition is variable exhaust valve
timing. This is not the first time VVT is used on an OHV engine –
General Motor's 3.9-liter OHV V6, for example, uses variable cam
phasing on its single camshaft. At high rpm it advances the intake
valve opening, but because the same camshaft also acts on the exhaust
push rods, the timing of exhaust valve opening is also brought forward.
This mean the GM engine enjoys very limited benefits from the variable
valve timing. In contrast, Chrysler's design uses a so-called
"cam-in-cam" construction, that is, a solid intake camshaft located
within a hollow exhaust camshaft (note: most magazines said vice-versa,
but my info comes from SAE's journal "Automotive Engineering
International" which is more trustable). The hollow exhaust camshaft
can rotate for a range of 36 degrees in relation to the inner intake
camshaft. This allows the use of very aggressive intake cam lobes
without hurting low-speed combustion quality and emission. The
"cam-in-cam" mechanism is a clever design, as it is reasonably
effective, cheap to produce (only one cam-phaser is required) and
easily compatible with existing OHV engines.
Performance is one matter. How to put the performance down
the road is another matter. Viper used to be praised for muscle car
performance but also criticized for muscle car handling. Therefore
Chrysler also took this opportunity to improve its chassis. Firstly,
the Tremec T56 6-speed gearbox is not only strengthened to handle the
extra power, but also gets modified synchromesh and reduced shift
travel. Now it requires far less effort to operate, although you still
won't describe it as "butter slick". Secondly, the previous heavyweight
clutch has been replaced by a low-inertia twin-plate clutch, which
lightens the pedal a lot. These two changes made the new Viper more
friendly to its driver. Thirdly, a new GKN speed-sensing limited-slip
differential has been adopted to improve traction through corners.
Fourthly, the suspensions get slightly stiffer springs, dampers and
anti-roll bars. Negative cambers and front caster angle increased.
These changes increase roll resistance and cornering grip. To
compensate for the negative effect on ride comfort, it replaces the
previous Michelin run-flat tires (whose stiff sidewalls hamper ride
quality) with new Pilot Sport 2 tires. Finally, the bodyshell of Viper
gets reshaped spoilers and additional ventilation louvers on the bonnet
to increase high-speed downforce. 
The biggest sensation of the Viper is still its power and
speed. However, now the handling has become a supporting role to them
rather than working against them. You will find the ride a little
smoother, the brakes a little stronger and the aforementioned gearshift
and clutch make it easier to drive fast and slow. But the biggest
difference is the chassis dynamics – the new Viper is more eager to
steer into corners because there is less understeer built into the
chassis. This is made possible by the improved poise, grip and
cornering traction, so Chrysler no longer needs excessive understeer to
tame the beast. At the limit, the Viper is also less easier to
oversteer.