SCIAC
From BG-pedia
UCLA and the
Southern California Intercollegiate Athletic Conference
UCLA had not always been in the Pac-10 Conference. Its first foray into conference play was in the Southern California Intercollegiate Conference (SCIAC). They played in the SCIAC from 1921 through 1927.
The members of the conference during UCLA's tenure there were Caltech, Occidental, Pomona College (now known a the Pomona-Pitzer Colleges), Whittier College, and Redlands. San Diego State would later join in 1926.
The conference still exists today with the original five colleges still members. More information about this conference can be found here.