To create the Cadillac STS-V, engineers dropped a supercharged 4.4-liter V8 into the engine bay, a heavily massaged motor making 469 horsepower and 439 lb.-ft. of torque, 90 percent of which peaks between 2,200 and 6,000 rpm. For those keeping score, this power output makes the STS-V the most powerful production Cadillac in history. An all-new six-speed automatic transmission sends the power to the rear wheels, producing acceleration to 60 mph in less than five seconds.