@Adolf Hamsterit's more for the noise reduction and less for aoe (though that is part of it), and I'd rather not be covering the vents on my piston head if possible.
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Adolf Hamster
might have to go manual then, although noise reduction on an aeg isn't a topic i've spent much time on (due to hpa quiet=best quiet).
aoe isn't a magic "for X gearbox type use Y distance" kinda thing, you need to be checking and if necessary adjusting on a per-gearbox basis.