"The blue car in the foreground #235 is Ferrari 500 Mondial 0438MD of Porfirio Rubirosa.  So it is Santa Barbara, September 5, 1954."

(10-23-08   From Michael Jacobsen:

"Duffy Livingston in the Eliminator is shown at the September, 1954, Santa Barbara race here, so obviously Agoura was not his first (he also ran at Torrey prior to this).   In the photo above Rubirosa leads in the Mondial, Bill Stroppe is on the inside and there is a red J2X Allard (Lytle or Ives 
or?). Stroppe ran away from the field the previous year (until hitting the ditch at 2) but DNFed this time. "