PORSCHE RACING HISTORY1985 - Columbus IMSA GT
5 October 1985 - Columbus, Ohio Street Circuit, USA
Chester Vincentz 4th in a Porsche 934, behind the winning Pontiac droven by Steve Millen
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 91 | Porsche 934 | 009 00030 | GTO | Chester Vincentz (USA) | Electrodyne Performance | 4th | 4th | 8th | 36 laps |
| 31 | Porsche 911 | GTU | Mark Altman (USA) | Altman Bros Motor Racing (USA) | 14th | 6th | 25th | 33 laps | |
| 29 | Porsche 914/6 | 914 043 0538 | GTU | Earl Roe (USA) | Earl Roe (USA) | 21st | 11th | 29th | 32 laps |
| 73 | Porsche 911 | GTO | John Higgins (USA) | John Higgins (USA) | 41st | 20th | 23rd | 5 laps - DNF | |
| 64 | Porsche 911 Carrera RSR | GTO | John Hulen (USA) | John Hulen (USA) | 43rd | 21st | 22nd | 0 laps - DNF |
IMSA - International Motor Sport Association
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