Premier Deep Hole Drilling has recently completed the drilling of an engine block for a very rare classic Aston Martin racecar.
Enthusiast Jonathan Dormer is funding the rebuilding of one of the rarest Aston Martin race cars, a DBR2. Paying unwavering attention to detail, he has rebuilt one of the two original multi tubular space-frame chassis, with the suspension and braking systems also being completed to original specification. Now the focus is on the engine, with a new block being sand cast to the original design.
Owner of Aston Martin engine builder and development engineering specialist JMB Services, Peter Bond, explains: "The block is cast from aircraft grade aluminium, we skim machined some flat datum faces on it before it is sent to Premier Deep Hole Drilling in St-Albans. While we can machine most parts here, we do not have the deep hole drilling equipment, knowledge or experience of the staff at Premier."
The engine block has a cast in main oil feed galley which needs to be drilled through. As the oil galley passes through the most intricate parts of the casting there is a risk of porosity, so the decision was made to drill the feed hole before any other machining operations were carried out. Premier's managing director, Stuart Grant, says: "A 19 mm diameter hole had to be drilled through the 747 mm block to form the main oil feed galley.
"Because the oil galley is close to the surface across the aluminium block, there is no allowance for the drill to vary from the intended trajectory, so we drilled it from both ends to meet in the middle. One end was drilled and then the block was set-up on the machine by referencing the initial entry point and feeding in directly opposite. The positional control on the machine was used to ascertain the position accurately, as the faces on the cast block were not accurate enough for us to use."
The DBR2 was originally created from a short lived Lagonda project, known as DP166 (DP for Development Project). Using the two DP166 chassis, Aston Martin owner, David Brown's racing department modified the cars with bodies similar to those from the DBR1, except larger and more aerodynamic. These cars would be christened DBR2/1 and DBR2/2.
For an engine, the new Tadek Marek-designed 3.7L straight-six from the newly launched DB4 road car was initially installed. For the 1958 season, the engine was enlarged to 3.9L, then again with a 4.2L engine later in the year to produce 298 bhp in a vehicle weighing just 800 kg.
DBR2/1 initially began competition at the 1957 24 Hours of Le Mans, where it unfortunately retired with a gearbox failure. Its only notable success for 1957 was at the Daily Express Trophy at Silverstone Circuit, driven by British racer Roy Salvadori, who set a new sports car lap record of 98.48 mph. He also won the 1959 24 Hours of Le Mans driving for Aston Martin with team mate Caroll Shelby
For the 1958 season, the FIA limited the engine capacity for the World Sportscar Championship to just 3L. The sudden change in the regulations left the DBR2, along with Jaguar D-Type, Maserati 450S and the Lister-Jaguar Special, unable to compete in international races. So, the DBR2 was relegated to non-championship British, European, and American events that permitted the larger capacity cars.
For 1958, the DBR2's programme was expanded, including the upgrade to the newer 3.9L engines. DBR2/1 won both the Sussex Trophy at Goodwood and the British Empire Trophy at Oulton Park, driven by Stirling Moss in both wins. After finishing 2nd and 3rd at Spa behind a Lister-Jaguar, Aston Martin decided to concentrate on the DBR1 for Europe, while both DBR2s were upgraded to the 4.2L engines and transferred to America where they could compete easier with larger engine capacities. George Constantine drove DBR2/1 to victories at Lime Rock and Marlborough before the end of the season.
Continuing in the United States in 1959, the cars again took victory in New York and twice in the Governor's Trophy at Nassau in the Bahamas, driven by George Constantine and Stirling Moss. This was the last ever works entry of an open cockpit Aston Martin, and both cars were then returned to Aston Martin in 1960, after two relatively successful seasons and were subsequently sold to privateers.
Author: Andrew Allcock