Billed as the quickest, most powerful Jeep ever, the 2006 Grand Cherokee SRT-8 is more capable on the road than it is off road. With a 6.1-liter V8 producing 415 horsepower and 410 lb.-ft. of torque, this is one Jeep that should be taken seriously. The Grand Cherokee SRT-8 rolls on twenty-inch rims and Goodyear performance tires, running an estimated 0-60 acceleration time of under five seconds.