To say that the Jaguar XJ12 is a rare bird would be an understatement. It was first available in 1972-73 as a Series 1, and only 3,228 were made. 16,060 Jaguar XJ12's were made from 1973-79. After that, it was dropped until 1994, when it came back briefly and sold only 1,828 over the next three years. That's a total of just 21,116 cars that carry the XJ12 nameplate. Many Jaguar XJ12 parts are unique to that vehicle, because of the engineering that went into its production. Dropping the V12 engine into the Series 1 and 2 chassis was difficult, and often experienced issues with overheating and fuel economy. Still, Jaguar was responsible for introducing the world's first production 4-door sedan with a V12 engine.