Do you remember when Honda first brought their motorcycles to the United Kingdom, and they ran their 'cc versus rpm war' advertisements? They were not the first ones to exploit the advantages of having a high revving engine with a low capacity. Riley beat them to it a good 60 – odd years earlier.
The Riley nine engine was the brainchild of Percy Riley whose father William ran a successful cycle business. William was not at all impressed by the prospects of those complicated, unreliable horseless carriage contraptions and when Percy, his middle son, began to take an interest in them he was quite dismissive.
Despite this Percy and two of his brothers pooled their resources, borrowed some cash from their obliging mother and set up in business to build engines for motorcycles. This was a decision which was going to have enormous impact on car engine design in the future.
By 1913, just before the First World War, Percy and three of his brothers started to build complete cars but there was a huge demand for aeroplane engines as Britain started to rearm. In common with many other engineering companies the Riley owned businesses concentrated on military contracts until 1918 and then engine, motor body and complete car manufacture restarted.
Throughout the 1920s the businesses prospered, with constant technical improvements, and by 1926 Percy had created the Riley 9 engine; easily one of the most important developments of the 1930s.
For the technically minded; the combustion chamber was hemispherical, set in a cast iron crossflow head with the valves set into it at 45° angles. These valves were operated by short pushrods and rockers, with twin high mounted cam shafts. The capacity was 1.1 litre; the aluminium alloy pistons in the four cylinders had a stroke of 95.2 mm with a cylinder bore of 60.3 mm.
For the less technically minded; the engine had the inherent advantages of a twin overhead camshaft design, but was less complex. This was an engine that would benefit from some extra tuning which could produce a far higher performance than the production engine was currently providing. Just as importantly; it was relatively cheap to buy as well.
In the hands of tuning specialists this engine was soon powering racing cars that were winning races all over the world.
One such enthusiastic tuner was John Godfrey Parry-Thomas, a onetime land speed record holder who also had the sad distinction of being the first to be killed during another attempt on the record. He was a part owner of a car design business based within the Brooklands racing circuit and he breathed his magic on the engine, fitted a lower body on it and set it within a chassis designed by himself and his assistant Reid Railton, another designer of high-speed vehicles.
High compression pistons were fitted, along with a modified exhaust manifold and twin carbs, which all added up to a power output of approximately 50 brake horsepower at 5000 rpm. This was enough to blow off most of the competition in the 1100 cc class races, including taking the 1932 Ulster Tourist Trophy, The Junior Car Club 1000 mile race at Brooklands and the Rudge Whitworth Cup at Le Mans in 1934.
It was an exciting car to drive as well. With the seats only 6 inches off the ground not only was roadholding improved considerably but the sensation of speed for the drivers was exhilarating!
Sadly Parr-Thomas died in 1927 on Pendrine Sands in Carmarthen Bay whilst trying to wrestle back is land speed record which Malcolm Campbell had broken only a few weeks earlier; But Reid Railton was able to take over and complete the project.