According to Car and Driver, the Challenger concept does indeed have a 6.1 Hemi with 425 hp, 420 lb-ft of torque, and a six-speed manual transmission. So geared, with its 4,100 pound weight, it can do 0-60 in 4.5 seconds (with 20 inch wheels on front and 21 inch wheels on back), and runs the quarter mile in 13 seconds flat; top speed is 174 mph (limited by wind resistance), while gas mileage is estimated at 14 city, 20 highway, very good compared with the original Challenger.