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Engine: One reason for the long hood on a Viper is to fit that monster 510ci (8.4L) all-aluminum V-10 SRT engine. Start with an aluminum block with pressed iron sleeves and cross-bolted steel main caps with a 4.060-inch bore and a forged crank 3.96-inch stroke. Then multiply that cylinder volume by 10 rather than 8. Perhaps the engine's only weak point is the hypereutectic pistons, even with their 10.2:1 static compression ratio. Keith's engine is relatively stock mainly because with a 600 SAE factory horsepower rating, you don't need to make too much more power to be really dangerous. In addition to the horsepower, these motors are rated at 560 lb-ft at 5,000 rpm. What makes this engine interesting is the cam-in-cam variable-valve-timing feature. It allows the factory to move the exhaust valve independently of the intake by as much as 37 degrees. The factory does this mainly for emission and idle stability reasons, but moving the lobes can also increase overlap for better power. Because the Dodge engineers expected all Vipers to see serious track duty, the new engines also come with a trick swinging oil pump pickup assembly inside the factory cast-aluminum pan. The heads were also new in 2008 with a complete factory CNC porting that also includes the combustion chambers. Sitting on top is a twin electronic throttle body, two-piece intake manifold. One place Keith added a little spice was with a set of M&M Performance 1 3/4-inch headers mated to a custom 3-inch exhaust system connected to a set of DynoMax Ultra Flow mufflers downstream of the stock catalytic converters. Controlling everything is a Mopar Performance PCM.
Transmission: Assisting with the transfer of power is a Sachs twin 10-inch clutch assembly splined directly to a Tremec TR6060 manual six-speed gearbox. The transmission is the next generation improvement over the original T56 and features triple First gear synchros and doubles for the rest of the box. Another big improvement for this Viper box is 10 percent larger gears compared with the older T56.
Suspension: The '08 and '09 Vipers come with slick factory forged-aluminum upper and lower control arms in the front and rear along with redesigned springs, shocks, and antirollbar enhancements. But even that wasn't quite enough for Keith. Here is where he spent some time adding a set of Hypercoil 500 lb/in front and 700 lb/in-rated rear coilover springs. Next he added a set of Motor Club Sport shocks that also come with external fluid reservoirs that you can quickly spot when the clamshell hood is opened.
Brakes: You can't blast into a corner and expect to come out shiny side up without reliable brakes. The Viper engineers loaded up the latest Viper with a set of Brembo four-piston front calipers with 44/40mm diameter piston, dual-opposing calipers clamping on to a set of 14-inch Eurotech drilled and slotted full-floating rotors. The rears are the same Brembo/Eurotech combo but with slightly smaller rear pistons. Of course, the snake is also equipped with ABS, which makes standing on that brake pedal really easy without incurring the wrath of the lockup gods.
Tires/wheels: We wouldn't be surprised to learn that the first Viper drawing started with monster tires and wheels and built the car around the rolling stock. The factory rolls these cars on ludicrously large 275/35ZR18 front Michelin Pilot Sport Z tires up front mounted on 18x10-inch wheels, while in back, the rubber swells to 345/30ZR19 Pilot Sport Zs snapped over 19x13-inch wheels. Then there are the supersticky 305/30R18 Hoosier gummies mounted on 18x11-inch SSR wheels for the front, while on the back the Viper masquerades as a steamroller using a pair of barbaric 335/20R18 Hoosiers mounting equally immoral 18x13-inch wheels.
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