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First Look: 2008 Dodge Viper Coupe and Convertible
Bite me! Take that, Z06 and GT500-the big, bad Dodge reclaims the American horsepower crown
By Matt Stone
Photography by Wesley Allison
600. As in horsepower. @#$&%!
First-gen Can-Am racers put out about that much. Same for late 1960s NASCAR stockers. Mopar's vaunted Street Hemi of 1970-1971 was good for "only" 425-and that was in SAE gross terms. LS6 Chevelle, Shelby 427 Cobra, any street-legal pre-Enzo Ferrari? Save your breath for another argument, because none of their horsepower numbers starts with a "6." Lamborghini's new Murcilago LP640 packs just that many cavallini-but it tops $300K.
Oh, sure, there are one-off tuner toys running hand-grenade motors that claim big power-at least until their internals morph into shrapnel. Don't even ask if they'll run on pump gas, pass a smog inspection, or if that engine-block-shredding ker-blammo is covered under warranty.
Pictured here is the next chapter in the Viper's story. It may be hard to tell because, other than an aggressive hood and some shuffling of colors and wheels, the rest of the new stuff and all that power resides beneath the hood and skin.
Dodge set the bar high when the original Viper RT/10 hit the decks in 1992 packing 400 horses. Over the last decade and a half, its displacement and power output have grown by ladder steps to the current car's 505 cubic inches and 510 horsepower. Since then, Chevy's 427.6-cubic-inch Z06 and Ford's supercharged Shelby GT500-each ripped with a minimum of 500 horsepower-have arrived at the burnout contest. So this time, the Dodge's pony gain is a 90-for an even 600-subject to final SAE certification. The Street and Racing Technology (SRT) development team, a cadre of hard-core tire melters, has no intention of being one-upped.
The basis of the 2008 Viper (the 2006 model gets an extended run, and there is no 2007) is a powerplant that, short of its layout and basic architecture, is all new. There were numerous reasons for this substantial overhaul. The first was to improve emissions compliance. Another was to quell the engine's rough-and-tumble nature at idle. The team wanted to clean up the engine-bay packaging. And, of course, add more power and torque. It's still an OHV aluminum V-10-now at 8.4 liters by virtue of a 1mm bore increase-yet no area of the engine's makeup or ancillary systems has gone untouched.
McLaren Performance Technologies, Ricardo, and others consulted on the engine project. The fortified V-10's major tech coup is the addition of variable valve timing. SRT claims this to be the first use of VVT in a high-performance cam-in-block engine. The goal of varying the cam overlap is the ability to optimize it over a wider rpm range; the result, claims SRT, is a wider powerband with improved idle characteristics yet bigger power up the rpm range. The cam profile has higher lift and longer duration than the previous V-10s.
The cylinder heads are thoroughly reworked, with revised combustion chambers for smoother airflow and lower friction. The valves are larger, too, all of which brings 23 percent more flow on the intake side and a 12-percent exhaust-side flow improvement. Beneath those valves are revised flat-top pistons with floating pins and stronger con rods. Also unique is the swinging oil pickup, developed on the Viper Competition Coupe, which moves within the oil pan to ensure the pump doesn't suck air during hard cornering. Even the oil filter is new.
Big changes for the intake system: It's now a two-piece manifold/plenum design, with smoother intake passages and surfaces throughout. Dual electronic throttle bodies replace the previous single unit. The cold-air intake has been revised for higher flow, lighter weight, and better NVH. The previous Viper's electrical architecture and engine-management system have been scrapped in favor of new hardware. Each cylinder gets its own coil pack mounted to the valve cover.
Team Viper (as originally called) has wrestled with the car's exhaust system since the beginning. Sidepipes were part of the car's DNA from its inception, but the first-generation's noncrossover-equipped system made the V-10 sound like an industrial vacuum cleaner. Second-gen cars routed the pipes out the back, which sounded better, but wasn't as cool. Sidepipes came back for 2003, with a crossover system that ran beneath the seats. They got the sound right-but turned the interior into a convection oven. The 2008's pipe job does away with the previous X-pipe setup, curing the heat problem and sounding exotic at the same time.
Changes continue aft of the crankshaft. A new dual-disc clutch pack has 18 percent less inertia, which will make the engine rev quicker than before. It also has a higher thermal capacity and reduced pedal efforts. This new flywheel/clutch/pressure-plate assembly can handle more than 600 pound-feet of torque-important, as the new 8.4 grinds out 560 pound-feet at 5000 revs. The latest Tremec six-speed (now known as the TR6060) also has increased torque capacity, and the synchro system is redesigned. Triple-cone synchros are used for first and second gears, with double-cone synchros for gears three to six; this is a considerable advance over the old Tremec T56, which used double cones for the first two gears and single cones for third through sixth. The result of all this, plus a revised shifter, should be quicker shifts, quieter operation, and longer transmission life.Further aft, the Dana M44-4 rear axle is a carryover piece, but packs a new GKN Visco Lok speed-sensing limited-slip differential, which will make it easier to put more of the power to the ground more often. Although the interior looks much the same, it benefits from new driver and passenger side-airbag systems. The frame itself and the suspension are carried over from the 2003-2006 models. And-rejoice!-they've done away with the Viper's run-flat tires. The change is aimed at better handling response, due to more driver-oriented tire-casing designs and reduced unsprung weight.
In keeping with the notion that form follows function, SRT focused most of its effort and product-development dollars into stuff that'll make the Viper go faster and run better. But a few pennies were spent on things you can see.
The biggest visual clue to the evil that lies beneath is a new louvered hood that looks aggressive and increases engine-bay airflow. There's a new optional wheel design called Razor. The color combinations are increased to eight; among the new ones are Shakespeare Green (hmmm), Viper Violet (more hmmm), and Bright Orange. Body styles are unchanged from the current coupe and roadster configurations.
The Viper remains a halo car for Dodge, more about bragging rights and magazine covers than big volumes. Sales have loafed along at an average of around 1700 units a year for the last half decade. One wonders how long the car will remain viable and in demand without a major reinvention. But SRT insists there's a business case to support it; hence, the huge engineering investment made in the 2008 models on these pages. The original Viper was one of the first cars to demonstrate that a large, modern-day OEM can build and deliver a low-volume niche product. So far, it continues to prove the point.Sales, schmales. Right now, the only number that matters is 600.
THE BIG ENGINE THAT CAN
# 1 Two-piece intake system all new, features dual throttle bodies
# 2 Individual coil packs reside atop valve covers; appearance neatened by cast "coil covers"
# 3 Air box has improved flow, better NVH, lighter weight
# 4 "VENOM" engine-controller system thinks faster than before, connects to CAN bus, meets OBD II
# 5 "Air gap" headers are double-walled for quicker catalyst light-off and better thermal characteristics
# 6 Revised cooling system more efficient than before
# 7 Platinum-tipped spark plugs
# 8 You can't see it, but the new transmission is plumbed for add-on external oil cooler
# 9 Valvetrain now capable of 6400 rpm
# 10 Lifters lighter by 28 grams each
# 11 Water jackets revised for increased coolant flow to heads
# 12 Compression ratio increased to 10.2:1 (from 9.6:1)
VIPER HORSEPOWER THROUGH THE YEARS
1992 - 400 hp: The Viper is born in roadster-only form. 400 hp from the original 8.0-liter V-10, which shares basic design with Ram truck engine.
1997 - 450 hp: The "Copperhead" V-10 is revised and uprated to 450 hp, although displacement remains the same. GTS Coupe joins lineup.
1998 - 460 hp: Commemorative GT2 edition Viper coupe gets minor intake-system mods that up horsepower output to 460 hp. ACR models get the same bennies.
2003 - 500 hp: Displacement grows to 8.3 liters for the mostly all-new Viper roadster. Horsepower now at 500 hp, putting Dodge first into the modern-day 500-hp club.
2008 - 600 hp: If bigger is better, the new Viper will be the best at 8.4 liters and an overachieving 600 hp. What's next, Warp Drive? It doesn't matter, just don't expect overhead cams
2008 DODGE VIPER
VEHICLE LAYOUT: Front engine, RWD, 2-pass, 2-door coupe or conv
ENGINE: 8.4L/600-hp/560-lb-ft (est) OHV 20-valve V-10
TRANSMISSION: 6-speed manual
CURB WEIGHT: 3400 lb (MT est)
WHEELBASE: 98.8 in
LENGTH x WIDTH x HEIGHT: 175.6 x 75.2 x 48.6 in
0-60 MPH: 3.6 sec
EPA city/hwy fuel econ: Not yet rated
ON SALE IN U.S.: Mid-2007 |
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