These cars took part in the Maserati UK Race for Pre-1966 Grand Prix & Tasman Cars at the Coys International Historic Festival meeting at Silverstone in July 1999.
They're the BRM P261s of Paul Alexander (no. 14) and Bruce McCaw (no. 46) - the latter being driven in the race by Richard Attwood. The programme of the event said this about Paul Alexander's car:
Few models beyond the 1950s - let alone individual cars - enjoyed Grand Prix careers spanning several seasons, but BRM P261-5 has the distinction of having competed at the highest level from 1964-'68, in both 1500cc and three-litre Formula 1 guises.
One of three raced by Graham Hill in 1964, it excelled on the road circuits, finishing second in the French Grand Prix at Rouen and fifth in the Belgian Grand Prix at Spa. A back-up car in 1965, it contested the final 1500cc Grand Prix in Mexico with Jackie Stewart.
Privateer Bernard White's Team Chamaco Collect fitted it with a two-litre BRM 'Tasman' V8 for 1966, Vic Wilson taking it to fourth in the non-championship Syracuse Grand Prix. By Monaco, Bob Bondurant was in, the American finishing fourth and last in a race of attrition.
Innes Ireland placed fourth in the Oulton Park Gold Cup, and went on to win the US and Mexican GPs. David Hobbs ran it in the '67 British and Canadian GPs, and was back in '68 with a three-litre V12 engine installed. Sixth in Silverstone's International Trophy, Hobbs took a Honda drive for the Italian GP, where Frank Gardner gave 261-5 its last outing, but failed to qualify.
Superbly rebuilt to its two-litre specification by Hall & Fowler, 261-5 is finally winning races, 35 years on, with Paul Alexander.
On 31 August 2016 I showed photographs of Paul Alexander's car at the 1992 Richard Seaman Memorial Trophies meeting at Oulton Park.