The Cadillac Sixteen dared to look the way it did and had an engine big enough to accommodate an entire bedroom, making it a concept car to remember.

When something this gargantuan pops up on your screen, it's almost inevitable that it's sending out a message, screaming big engine. The Cadillac Sixteen was the quintessential American concept: huge, powerful and sexy. The concept was revealed in 2003 to the world at the Detroit Auto Show. It blew most people of their feet; an absolute show-stopper - and it came with a V16 engine under the long bonnet. Having said that, it wasn't the first car with such a large engine. In 1930, Cadillac sold a car called the V-16, and it was perhaps one the most elegant and desirable cars built for 10 years, limited to just 4,000 units. The pre-war period wasn't starved of powerful cars that looked great, either. This concept was built by General Motors in honor of the vintage Cadillac.

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The Cadillac Sixteen is the sharpest-looking sedan, even after all the new Bentleys and Mercs. There is, quite possibly, nothing that looks as good as the Sixteen Concept, primarily because it was just that - a concept. The Sixteen is unbelievably long at 18-feet, and it has those cutting-edge lines of a luxury yacht. Cadillacs have looked great for generations, but the Sixteen found its way into the hearts of many American car enthusiasts. It's near impossible to ignore the 24-inch polished aluminum wheels. Notice how the design team never bothered giving it B-pillars and door handles. Sleek headlights and tail lights dominate the front and rear. It is believed that the Sixteen has 20 coats of paint; 19 of which give it the thin pearl paint finish.

The Sixteen left no stone unturned on the inside either. The cabin was packed with premium materials that included glass leather, aluminum and wood. The Tuscany leather seats were hand-stitched and looked as enticing as luxury couches at home. Some niche features included a Cadillac logo made of solid crystal for the steering wheel and a Bvlgari clock mounted atop the dashboard.

The Sixteen Concept was powered by a 32-valve, 13.6-liter, 16-cylinder engine. The last time we checked, only aircrafts and locomotives were powered by such a monstrosity of a motor. The engine claimed to make 1000hp and 1000 lb-ft of torque. However, since it was only a concept, top speed was limited to only 40mph. The engine was based on GM's fourth-generation LS architecture and featured Displacement on Demand technology (or cylinder deactivation as they call it today) - it shuts down half cylinders, which helps in saving fuel. This tech trickled down onto Cadillac's production models that followed later and other cars as well. Katech Inc. designed the engine solely for the concept. Mated to the engine was a redone 4-speed Hydra-Matic gearbox. It's a pity we'll never know how fast it would've been in a straight line.

All-wheel steering systems are not new, not at all. The Cadillac Sixteen featured the same, called Quadrasteer. Having to turn such a big car meant the rear wheels had to turn in the opposite direction to the front wheels at low speeds. At high speeds though - or in this case - 40mph, all wheels steered in the same direction for improved stability and grip.

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Cadillac's fans were gutted the moment they knew this wasn't going to make it to production. The Sixteen was destined to appear as a showcar, and at most, a working prototype. But the Sixteen lived on in the design language that inspired many Cadillac models that followed, including SUVs. The engine, on the other hand, died, and that was that. The Cadillac Sixteen, then, was a lot like Bridget Fonda from Hollywood: beautiful and cherished, but had a short-lived career.

Rehan got published for the first time at the age of 17, having written a feature on a Triumph Herald in print. He uses his writing as a tool to express his fondness for all things automotive even today, aged 28. Collecting scale models is a hobby close to his heart, and he wishes to sprinkle pixie dust on them only to see them grow into full-sized cars. He now represents HotCars.com.