Harris Westminister HWSF offers

I am a private school student and I'm applying to harris. I have the entrance exams on Saturday, and since I'm in private school I understand that it is harder for me to get in. I am also in the middle of my mocks right now so I don't know how much time I will get to spend revising for the entrance exams. Assuming I don't get a conditional offer and I decide to apply on results, day what grades would I need to study there? I am currently predicted all 9 and 8