British Racing Motors V16 Grand Prix Racer. Click image to enlarge
Story and photo by Bill Vance
Sixteen-cylinder engines exude an exotic aura. Manufacturers who have offered production V16s, including America’s Cadillac and Marmon, are rare. Most 16s were built for racing, and out of about a dozen attempts, some produced only a single example. While the promised smoothness was usually achieved, the attendant complexity was often overwhelming.
Following World War II, a consortium of British manufacturers decided that Britain’s prestige required that it compete in Formula One racing. Undeterred by the intricacy of the 16-cylinder layout they proceeded with one of the most exotic V16s ever conceived. Its mission would be to win international prestige for Britain. Alas what promised much produced little.
It was the idea of Englishman Raymond Mays, and it had emerged before the Second World War when Mays was racing British E.R.A.s in Europe’s sub-Grand Prix level races. He was chagrined that a major auto producing nation like England didn’t produce a top level racing car.
He noted the national pride that other counties enjoyed from the success of their Grand Prix racing teams. Germany’s state-supported Auto Union and Mercedes-Benz cars raised national pride to the level of a propaganda tool, while demonstrating the superiority of German engineering.
Grand Prix racing was suspended during the war, but as hostilities neared their end, Mays set out to create a competitive British Grand Prix car. He and engineer friend Peter Berthon formed a company called Automobile Developments Ltd. Their aim was to appeal to British pride, and rally the best British engineering available to produce a winning car.
Mays canvassed the British auto industry for financial and technical support. Among early responders were steelmaker Rubery Owen, Lucas Electric, Standard Motor Co., and Rolls-Royce. A war-weary nation caught the spirit, providing both money and expertise. Ultimately some 350 firms would participate.
In 1947 the British Motor Racing Research Trust was formed to manage the assets. The Mays-Berthon company, Automobile Developments Ltd., became British Racing Motors Ltd., which would build the BRM Grand Prix car.
The Grand Prix series was formalized in 1950 as the Formula One world’s driving championship. It set an engine displacement formula which allowed displacements of 1.5 litres supercharged, or 4.5 litres unsupercharged.
BRM decided to develop the BRM Type 15 to comply with the 1.5-litre V16 supercharged formula. They chose a very complex and ambitious design, a 135-degree V16 engine configuration based on the theory that the larger the total piston area the greater the power potential.
Dividing 16 cylinders among 1496 cc meant extremely small dimensions; the bore and stroke were 49.5 by 47.8 mm (1.95 X 1.88 in.). Pistons were about the size of egg-cups! And at the targeted 12,000 rpm, those tiny pistons would be stopping and starting 400 times per second. Crankshaft twisting with the long shaft was controlled by taking the power from a gear in the middle of the crankshaft and transferring it to a shaft under the crankshaft. This shaft sent power to the rear wheels through a four-speed transmission.
The 32 valves were operated by gear-driven, twin overhead camshafts, and for compactness the valves were closed by hairpin springs. With the two-stage Rolls-Royce centrifugal supercharger boosting to an astonishing 70 pounds per square inch, the V16 was expected to develop 550 to 600 horsepower.
The design was completed in 1947, but parts delays kept the first car from being finished until late in 1949. Development problems continued, but a BRM was finally entered in Britain’s Daily Express Trophy race in August 1950.
Having missed official practice, BRM driver Raymond Sommer had to start at the back of the grid. When the flag dropped, Sommer’s car lurched forward, then stopped, having sheared its drive axles. It was a humiliating day for British engineering, and long suffering British racing enthusiasts who soon began heaping contempt on the effort.
Although the car was improving, it never reached its full potential, and didn’t win one major Grand Prix, although it was victorious in some minor races. Apart from continued engine unreliability which kept it out of several GPs, the very sharp power peak and sudden boost characteristics of the centrifugal supercharger made it difficult to drive.
Then at the end of 1951 the 1.5-litre BRM was rendered obsolete when the racing formula was unexpectedly changed to 2.0 litres unsupercharged. But even before that, in mid-1951, Ferrari’s normally aspirated 4.5-litre engine had vanquished the formerly supreme 1.5-litre, supercharged Alfa Romeo straight-eights, demonstrating that the era of the thirsty, highly stressed, supercharged 1.5-litre was closing.
The BRM 1.5-litre V16 was a brave but unsuccessful attempt to bring Grand Prix prestige to Britain in the years after the Second World War. It failed for many reasons, including design flaws, mechanical complexity, shortage of funds, and some questionable management.
The BRM V16 entered only four Formula One races before the 1.5-litre formula expired in 1951. It failed to leave the starting line in two of them, and finished only one.
BRM would try yet another 16-cylinder engine in the 1960s, an H-16, essentially one flat-8 on top of another. It too was fraught with problems, although it did manage to win one Grand Prix. Britain would achieve Grand Prix success, but it was with less complex machinery than 16-cylinder engines.