One of the best-known artworks at the Los Angeles County Museum of Art is Edward Kienholz’s “Back Seat Dodge ’38,” an assemblage that includes two faceless figures made of chicken wire and engaged in a sexual encounter in the back of an actual vintage car. Although it’s almost 40 years since the work first went on display, it still carries a certain titillation factor. In 1966, it sparked a controversy at the newly established museum and was declared pornographic by the county Board of Supervisors.