Hi Lucas. Your exams can have a very strong impact on your SAC scores. This will depend highly on your class rank and strength of your school's subject cohort. Have a read of this article under the SAC Moderation section — it should explain everything.
It's pretty complex and it relies on information you likely don't have, so it's be very difficult for you to predict how your exams will scale your exact SACs. I'd recommend having a chat to your teachers and getting their advice on how to improve your SACs. If you're really worried then they may be able to tell you your class rank, however this is up to their discretion. Best of luck.
