PERFORMANCE TEST

Hennessey Venom 550 GTS

Listen to the conversations in general aviation airport coffee shops.  Sooner or
later someone will describe the treacherous nature of one light aircraft or another
as a "doctor killer."  It's a vivid image of a weekend aviator in over his head with
a plane whose dynamics demand more skill than he can muster.  In the hands of the
untrained, Hennessey Motorsports' firebreathing Venom 550 GTS modification of the
Dodge Viper GTS comes perilously close to being the automotive equivalent of a "doctor
killer."

Motor Trend has perenially been at the forefront of the Viper scene and was the
first publication to test not only Hennessey's unholy Venom 500 and 550 packages,
but also the Texas-Tuner's 8.5-liter/635-horsepower Venom 600 upgrade to the RT/10.
The Venom 550 modifications on the Viper GTS's 8.0-liter V-10 consist of numerous
time-honored hot rodding tricks.  On the inhalation side, enlarged throttle bodies
take air past a modified intake manifold through ported cylinder heads with valves
retained by titanium, guided in bronze, and controlled by a specially ground roller
camshaft.

Once the 10.0:1 compressed charges have been ignited, waste gases pass through the
stainless steel headers and dual 3.0-inch-diameter pipes.  Hennessey-supplied DynoJet
chassis dynamometer figures show 493 horsepower and 508 pound-feet of torque at the
rear-wheels.  What that amounts to at the crankshaft, the company claims, is 585
horsepower at 5700 rpm and 596 pound-feet of torque at 4500 rpm-- 135 more horsepower
and 96 pound-feet more torque than Chrysler claims for an unmodified GTS.  Hennessey
will identically prepare your Viper's engine for $22,000.

Beyond the engine work, Hennessey added oversize 13.5-inch-diameter Alcon front disc
brakes, three-piece Speedline wheels, a short-throw shifter, five-point safety harnesses,
and a raging infestation of Venom logos.  Add it all to the modest $69,300 price of
the Viper GTS and the result is a $99,900 total.  Why not tip Hennessey's lot boy and
make it an even 100 grand.

The GTS is more forgiving than the first RT/10s, but it still can be a cruel mistress.
Add more to the mix, and the car is always just one throttle stab away from putting
its rear end where its front end should be.  With launches more precise than than a
brain surgeon's incision, the Venom 550 GTS missiled to 60 mph in just 3.9 seconds
and ate the quarter mile in just 11.9 seconds at 124.4 mph.  That's 0.2 seconds
quicker to 60 than stock and a full half-second quicker in the quarter mile.  Catapults
of this kind are usually performed flaps down with the carrier headed into the wind.

In real-world terms, that means the power simply overwhelms the Viper's chassis.  Letting
a teenage driver pilot this barbarian amounts to child endangerment.  Putting yourself
in the driver's seat (especially in the rain) without a few days of track time to
familiarize yourself with the car's potential is flat-out foolish.  But no matter
how much we warn you, this sort of intoxicating brutishness will no doubt have buyers
cramming Hennessey's order book.








This article was taken from the April 1997 issue of Motor Trend.