In the perpetual scuffle for supercar supremacy, there is no such thing as too much power, torque, or performance. After watching Chevrolet Corvettes, Porsches, and Ferraris scorch tracks across magazine covers, team SRT is keen to retaliate. Packing nearly twice the Ferrari F430's piston displacement, 50 percent more power than the original Viper, and a laundry list of refinements, Dodge's serpent stirs from a year's nap (there is no 2007 model) hungry for action.
Without flames, wings, or fender flares to draw attention to its business, the Viper has slithered to 600 hp. Michelin run-flat tires have been superseded by Pilot Sport PS2 rubber, and new forged, ten-spoke wheels are optional, but the only obvious hint that something is up is a more aggressively vented hood.
The 8.4-liter V-10 under that bonnet borrows pistons and connecting rods from SRT's 6.1-liter Hemi V-8 to rev higher and to hiss harder. Twin throttle bodies and mass airflow sensors feed a larger intake plenum. A compression ratio boosted from 9.6 to 10.2:1, larger valves, CNC-machined combustion chambers and valve bowls, and smoother ports all help squeeze more energy out of each breath. New hydroformed exhaust headers route spent gases through four catalytic converters and two resonators housed inside the Viper's side sills. Thanks to a new camshaft configuration (see Techtonics sidebar) and a smarter electronic controller, the world's largest sports car engine idles more smoothly and meets pass-by noise requirements without the 2006 model's cumbersome, crisscrossed exhaust pipes.
More low-end torque was the last thing the Viper needed, so powertrain engineers used this opportunity to extend the V-10's high end. Lifters and rocker arms are lighter and intake valve stems are hollow in support of a 6200-rpm redline. At 3900 rpm, the new torque curve sweeps past the old one while surging to a husky 560 lb-ft peak at 5000 rpm. The power plot crests at 6100 rpm with a 300-rpm cushion before fuel delivery is interrupted.
The added impetus in the engine room prompted various other upgrades. A swinging oil pickup keeps lubrication pressure stable during high-g operation. A new dual-disc clutch combines higher torque capacity with lower inertia and reduced pedal effort. The six-speed Tremec transmission has ten percent wider gears, higher-capacity synchronizers, and plumbing to ease the task of prepping this box for track battle. A new hydraulic-type limited-slip differential engages more progressively to minimize tail wiggle when accelerating out of tight bends.
To throw a bone to the Viper faithful, the SRT team has added five new exterior colors, two fresh center-stripe configurations, and four new ways to spec out the interior trim.In the power-to-weight game, adding 90 hp while holding the weight gain to three pounds hurtles the Viper a notch up on the Corvette Z06. Which of these will be the first to break the 125-mph quarter-mile and the 200-mph top-end barriers? The only way to know for sure is to stage a showdown, a top-priority item on every tester's to-do list.