The 40/50 hp engine mixes the conservative and the advanced. The use of two three-cylinder blocks was archaic (by post-World War I standards), as were the fixed cylinder heads and exposed valve gear. But the drilled and fully pressure-fed crankshaft-with seven main bearings-put Rolls-Royce ahead of the game. Initially 7,036 cc, engine capacity was increased to 7,410 cc in 1909. Output rose over the years from an estimated 48 bhp to approximately 75 bhp on later cars.