Originally Posted by mister p
They were injected weren't they. Arguably a better machine than the Spit.......
certainly more advanced "While the conventional mechanical superchargers consisted of one or two compressors driven via a two-speed gear, Daimler-Benz utilised an ingenious barometrically controlled hydraulic clutch which adjusted the compressor speed and thus the charging of the engine according to the needs at a given altitude."
Taking into account the age of the Merlin design and its relative small displacement this two-stage inter- and after-cooled engine was a superb machine. In comparison with the German engines the Merlin was lighter due to the relative abundance of metals for making light alloys. When comparing outputs one should also bear in mind that the allies were well supplied with high grade fuels (100/130/150 octane). The Germans had to make do with 87, 92 or 96 octane, the higher grade fuels being especially scarce. ADI was used by both sides in the later stages of the war.
The Merlin 60 series were put into service in the late summer of 1942, around the same time that the DB 605A-1 went into service. The high altitude performance the Merlin 60 series was superior to the DB 605A-1. This superiority lasted into 1944 when the new AS and D sub-types went into service. These late sub-types equalled or bested the high altitude performance of the Merlins (Rolls-Royce and Packard) perhaps with the exception of the Mark 70. When GM-1 was used the picture changed thoroughly in favour of the DB 605.
The DB 605 basicallly gave good low altitude performance, especially at sea level (read the discussion of the supercharging systems
). In this regard the DB 605A-1 was superior to the Mark 61, 63, 66 and 68 Merlins. The superiority of the late mark DB 605's at low and medium altitude was very pronounced when using MW-50 (AM, ASM), high octane and high boost (DB, ASB), high octane high boost