| Switzerland | 18 May | Piero TaruffiTAR | Ferrari | 62 | 3:01:46.100 |
| Indianapolis | 30 May | Troy RuttmanRUT | Kuzma Offenhauser | 200 | 3:52:41.880 |
| Belgium | 22 Jun | Alberto AscariASC | Ferrari | 36 | 3:03:46.300 |
| France | 06 Jul | Alberto AscariASC | Ferrari | 77 | 3:00:00.000 |
| Great Britain | 19 Jul | Alberto AscariASC | Ferrari | 85 | 2:44:11.000 |
| Germany | 03 Aug | Alberto AscariASC | Ferrari | 18 | 3:06:13.300 |
| Netherlands | 17 Aug | Alberto AscariASC | Ferrari | 90 | 2:53:28.500 |
| Italy | 07 Sep | Alberto AscariASC | Ferrari | 80 | 2:50:45.600 |