PORSCHE RACING HISTORY1973 - IROC Riverside 1
27 October 1973 - Riverside International Raceway, USA
Mark Donohue wins in a Porsche 911 Carrera RSR
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 2 | Porsche 911 Carrera RSR | 911 460 0025 | Mark Donohue (USA) | Roger Penske (USA) | 1st | 1st | 30 laps | ||
| 7 | Porsche 911 Carrera RSR | 911 460 0116 | Bobby Unser (USA) | Roger Penske (USA) | 2nd | 5th | 30 laps | ||
| 3 | Porsche 911 Carrera RSR | 911 460 0016 | Peter Revson (USA) | Roger Penske (USA) | 3rd | 2nd | 30 laps | ||
| 4 | Porsche 911 Carrera RSR | 911 460 0059 | George Follmer (USA) | Roger Penske (USA) | 4th | 12th | 30 laps | ||
| 6 | Porsche 911 Carrera RSR | 911 460 0075 | Denny Hulme (NZ) | Roger Penske (USA) | 5th | 4th | 30 laps | ||
| 8 | Porsche 911 Carrera RSR | 911 460 0050 | A. J. Foyt (USA) | Roger Penske (USA) | 6th | 6th | 30 laps | ||
| 10 | Porsche 911 Carrera RSR | 911 460 0042 | Richard Petty (USA) | Roger Penske (USA) | 7th | 8th | 30 laps | ||
| 12 | Porsche 911 Carrera RSR | 911 460 0090 | Roger McCluskey (USA) | Roger Penske (USA) | 8th | 10th | 30 laps | ||
| 5 | Porsche 911 Carrera RSR | 911 460 0111 | David Pearson (USA) | Roger Penske (USA) | 9th | 3rd | 28 laps - Oil Leak | ||
| 11 | Porsche 911 Carrera RSR | 911 460 0085 | Gordon Johncock (USA) | Roger Penske (USA) | 10th | 9th | 28 laps | ||
| 9 | Porsche 911 Carrera RSR | 911 460 0035 | Bobby Allison (USA) | Roger Penske (USA) | 11th | 7th | 14 laps - Transmission | ||
| 1 | Porsche 911 Carrera RSR | 911 460 0100 | Emerson Fittipaldi (BR) | Roger Penske (USA) | 12th | 11th | 9 laps - Accident |
IROC - International Race of Champions
Previous 1973 - Can-Am Laguna Seca Next 1973 - IROC Riverside 2