I just changed my oil myself and it took a total of around 8.4L to fill. The oil level marker is right at the top arrow, so I would say 8.25 should do you just fine. I did let the oil drain for a while so it may take less if you do not let the oil drain completely from the openings in the oil pan.
2012 Audi R8 V10, 6MT, Suzuka Gray, Capristo X-Pipe, Klassen M52R, GMG springs, R8 GT tails, Satin Black badges
2012 Audi A6 3.0T Prestige, Moonlight Blue
2015 BMW X5 35d, Mineral White
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