1915 Chicago Auto Club Trophy Race
21 August - Elgin, IL: 36 laps x 13.4315 km = 483.536 km

Pole Position: N/A
Fastest lap:   Earl Cooper     6:26

Results:

1  8 Earl Cooper        Stutz        4:01:32
2  6 Gil Anderson       Stutz        4:05:04
3 11 Barney Oldfield    Delage       4:09:55
4 10 Tom Alley Ogren    Dusenberg    4:14:29
5  7 Eddie O'Donnell    Duesenberg   4:15:40

Retirements:
   3 W. W. Brown        DuChesneau   25 Brkn connecting rod 
   5 Pete Henderson     Duesenberg   22 Out
   4 Ralph DePalma      Mercedes     21 Broken rocker arm
   2 Frank Justin       Cornelian    11 Broken water line

Race Note
1) Open for cars with maximum 300 cu inch