| Senior Men 400 Metres HEAT 1 (Motspur Park, 12 May) | 1 | | Rod Milne | (Thames Valley Harriers) | 49.5 | | | | | 2 | | Allan Cord | (Herne Hill Harriers) | 50.4 | | | | | 3 | | G Henry | (Hercules Wimbledon AC) | 51.9 | | | | | 4 | | D Cleary | (Mitcham AC) | 52.5 | | | | | 5 | | A Wigley | (Mitcham AC) | 52.8 | | | | | 6 | | Jonathan Owen | (Hercules Wimbledon AC) | 53.5 | | | | |
| | | Senior Men 400 Metres HEAT 2 (Motspur Park, 12 May) | 1 | | Bob Benn | (Croydon Harriers) | 50.6 | | | | | 2 | | R Lindo | (Hounslow AC) | 51.1 | | | | | 3 | | G Sagar | (London AC) | 52.3 | | | | | 4 | | E Bell | (South London Harriers) | 52.5 | | | | | 5 | | A Bennett | (Epsom & Ewell Harriers) | 53.4 | | | | | 6 | | R Chapman | (South London Harriers) | 53.5 | | | | | 7 | | D Moffat | (Woking AC) | 56.2 | | | | |
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