The Cadillac Sixteen is a high performance concept car first presented by Cadillac in 2003.
The vehicle is equipped with a Cadillac proprietary-developed 32-valve V16 engine displacing 13.6 liters (~830 cu. in), which was exclusive to the Sixteen model only, it is mated to a four-speed, electronically controlled, automatic transmission driving the rear wheels. The engine features fuel-saving Active Fuel Management "Displacement on Demand" technology, much improved from its notorious ancestor, debuting in 2004 on some 2005 GM models. On the Sixteen, it would seamlessly shut down twelve cylinders in light driving, eight during strenuous driving, and only awaken the entire engine under full acceleration. With this type of system, the engine was capable of 16.65 mpg under normal conditions. The engine was said to produce a minimum of 1,000 horsepower (750 kW) and at least an equal amount of tourque at 1000 lb.-ft. using no form of forced induction. The car itself weighs about 2,270 kilograms (5,000 lb)