Car and Motorcycle

The vehicle is equipped with a Cadillac proprietary-developed 32-valve V16engine 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 torque at 1000 lb.-ft.using no form of forced induction. The car itself weighs about 2,270 kilograms (5,000 lb).

The Sixteen's custom interior
The car referenced the Cadillac V-16 of the 1930s. The actual design of the car was a combination of Cadillac's current "Art and Science" design theme and 1967 Cadillac Eldorado cues. Additional original design elements were provided by an in-house design competition led by GM Vice President Robert Lutz. The Sixteen has the Cadillac logo carved out of solid crystal on the steering wheel and a Bulgari clock on the dashboard.
Although the Sixteen fell short (narrowly, by some accounts)[citation needed]of production approval, its legacy is alive in Cadillac's future product planning. The subsequent generation of Cadillac products, particularly the revised CTS, have incorporated elements of the Sixteen's design. A scaled-down version of the car, referred to as the ULS (Ultra Luxury Sedan) or XLS, with a standard V8 and an optional V12 (the latter was to be called the Cadillac Twelve), has been rumored for production since 2005, but was shelved in favor of the Cadillac XTS.
Ever since the Sixteen was first unveiled there have been resurfacing rumors, speculation and high hopes of automotive journalists and aficionados about a possible very limited production of an exclusive Cadillac halo model such as the Sixteen as the "ultimate flagship" of the brand to sit even atop of the upcoming flagship, as previewed by the Ciel concept of late 2011
It was on the episode of Ride with Funkmaster Flex at the 2003 New York International Auto Show.
Also in 2003, Top Gear Reviewed the Cadillac 16 with its presenter James May in Series 2, Episode 10.