Next up in our series on the legendary “M” vehicles… the BMW M535i! Unveiled at the Frankfurt motor show in 1979, the M535i wowed the masses with it’s upgraded engine along with aerodynamic improvements. The M535i sported the same 3.5 liter in-line 6 engine as the E23 735i and E24 635i models. Unfortunately for drivers on this side of the pond, the engine was not available with a catalyst and did not meet U.S. emissions requirements. Perhaps, because of this, the M535i was only produced until 1981.