When did the pac 8 become the pac 10?

The Pacific-8 Conference, known as the Pac-8, expanded to become the Pac-10 in 1978 when it added two new members: Arizona and Arizona State. This expansion marked a significant change in the conference's structure, allowing for greater competition in various sports. The Pac-10 continued to operate under this name until it further expanded to 12 teams in 2011, becoming the Pac-12.