Whoever told you that is either a liar or misinformed. Neither your school ranking or your own subject rankings from last year will have any effect on your final HSC marks. They may give you a general idea of where everyone will wash up, but in no way will they impact on your marks. Rank-wise, it's only your overall rank for the HSC year (Term 4, Year 11 to Term 3, Year 12) that counts, and it counts for 50% of your final mark, so make sure you do your best to keep it high.
Scaling is calculated by comparing how everyone who does a particular subject achieves in all their other ones. For example, scaling for students doing Physics is calculated by looking at how well those students did in all their other subjects. Scaling uses the average of your raw examination and assessment marks, with no aligning taking place.
In short, nothing from Year 11 carries over.
I_F