The BMW E31 is the first generation of the BMW 8 Series. It is a grand tourer built by BMW from 1990 to 1999 powered by either a V8 or V12 engine. While it did supplant the original E24 based 6 Series in 1990, a common misconception is that the 8 Series was developed as a successor. It was actually in an entirely new model class aimed at a different market, with a substantially higher price and performance than the 6 Series.
BMW 850 CSi