The redesigned Viper returns as SRT Viper. It is powered by an all-aluminum, 640-hp, 8.4-liter V10 and has a standard six-speed manual. This SRT Viper is about 100 pounds lighter than the last model, and is designed to appeal to buyers of $100,000 vehicles who want super high performance along with an upscale interior and more civilized manners. Two versions are offered: the base and the more upscale GTS. The new chassis is said to markedly improve handling. The interior is also more upscale, something the last generation sorely lacked.