IIRC there's a phenomena sometimes referred to as "superknock" AKA (maybe, sometimes) Low Speed Pre Ignition, which some GDI engines seem to be especially prone to.
Long time since I read up about it, and the literature at that time was rather unclear, but it seemed (at least sometimes) to combine the two (normally/classically) separate phenomena of pre-ignition and detonation (though this distinction is widely disregarded).
I THINK perhaps pre-ignition initiated detonation, resulting in especially damaging conditions in the cylinder.
Fixes/workarouinds were low calcium oil and reduction of the turbo boost pressure. Dunno if it remains a significant problem, and I suppose, in the twilight years of the ICE, it doesn't matter much if it is, unless you happen to be affected.
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