Want a little Dodge Viper in your Challenger? Well, Mopar (Chrysler's performance division) has obliged. If you have almost $90K ($85,512 to be exact) you can get the 2011 Dodge Challenger Drag Pak, which has a Viper V-10 under the hood. The 8.4-liter V-10 isn't exactly the same as the engine in...