It is no accident that the Merlin has been the most successful Liquid cooled inline engine used in post war racing. By the end of its development it was as bullet proof as current technology could make it. Part of how the Merlin got to this position can be explained by the excellent supercharging and associated parts of the intake system that all work together to take advantage of the supercharger. Having provided the means of producing more power the mechanical engineers rigorously strengthened every component. This is the essence of how the engine became so strong. Of course it did not happen all at once.

Much myth surrounds the German fuel injection, but most people don’t understand how it worked or that it bore more relationship to a diesel engine fuel system than any modern type fuel injection system that all inject into the intake of the engine. The system used by Germany during the war on their large aero engines was a metered direct into the cylinder injection system. It suffered at times from poor atomisation and this lead to detonation and lower power levels. As boost pressures rose, these problems became more difficult to resolve.

The humble carburettor on the other hand worked by the low pressure on the intake drawing fuel into the engine. It was soon realised that the traditional float chamber type had some serious drawbacks in combat, but it had better mixture control and atomisation as the supercharger added agitation. The injection carburettor replaced the more traditional type and overcame the operational issues.

Again as boost pressure rose and 2 stage superchargers were used the process of injecting the fuel into the eye of the supercharger could lower the air/fuel change significantly lowering the detonation level and allowing more power to be produced. This was the very effect that MW50 had.

interesting information many thanks for posting it
regards vic