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 Grey| Dallas Performance Stage 1.5 Twin Turbo| 817whp pump| 950whp on 109 octane| GMG springs| Klassen M52R| Toyo R888R| GT Tails| GT wing| Black Optic Grille| CF everywhere| Satin black badges
2015 BMW X5 35d|Mineral White| Mocha
2017 BMW M3 ZCP| Mineral Grey