In 2016, Porsche added the 718 prefix to the Boxster and Cayman, creating the Porsche 718 Boxster and Porsche 718 Cayman. The change applied to the 982-generation cars and accompanied a major engine shift.
The 718 name revived Porsche’s racing heritage. The original Porsche 718 was a lightweight mid-engine sports-racing car powered by a four-cylinder boxer engine, and it won the Targa Florio outright in 1959 and 1960. Porsche used the historic designation to connect the modern road cars with that compact, efficient competition design.
The 2016 Boxster and Cayman also moved from naturally aspirated flat-six engines to turbocharged flat-four units in their regular versions. Base cars used 2.0-liter engines, while S models used 2.5-liter engines. The Boxster roadster appeared first in 2016, followed by the Cayman coupe later that year.
The numbers 981 and 987 are generation or internal designations, not the new marketing prefix. The 911 is a separate Porsche model line.