DB605AS info - need to determine WHERE and WHEN?

[Mermet]

Hi,

The letter "O" in DB 605 ASO, DMO, ASMO is for "Oktan-Selektor". This device permitted indifferently the use of B4 or C3 fuel.
On the late versions of the DB 605, i.e. DB 605 D, the O was replaced by B for B4 fuel and D for C3 fuel and MW 50, giving respectively the DB 605 DB and the DB 605 DC.
That was the same for the DB 605 ASB and DB 605 ASC which appeared at the beginning of 1945.
If you study the different engine WNr series you'll see that the engines with the suffix "O" have higher WNr than the first version to which they are attached : DB 605 ASMO have higher WNr than the DB 605 ASM, DB 605 DMO have higher WNr than DB 605 DM and lower WNr than DB 605 DB/DC, etc.
It's clear the suffix "O" is the letter and not the digit "0"... and means really "Oktan-Selektor".

Cheers,
JCM