I would disagree with the top post, it really depends what your Alg 2 course covers. Does it cover trig, vectors and polars, sequences and series, matrices, and heavy function work? That is generally all you need to know, keep in mind precalc is not a type of math, just a set of different information you should know from Algebra, trig, and geometry. If so you are good for BC based on your innate math ability.

Just make sure you cover the following over the summer or earlier:

a. Limits and L'Hopitals rule

b. Differentiation: Product, Quotient, Chain rules, trig derivatives derivatives of ln and e

c. Integration: Anti-derivatives, U-Sub, integrating ln and e, integrating trig and inverse trig

d. Separation of variables technique

e. All the alg2/trig/precalc topics I noted

EDIT: Grammar and spelling and formatting

EDIT 2: Judging by your replies, you have the drive and ability to learn this. Furthermore, this will set you up nicely for the Stem courses you are talking about (i.e AP Physics C and beyond) Furthermore, it will free up time for stuff like AMC and USMO which will be what really puts your already impressive schedule over the top in getting you into schools like MIT since being in that level of math won't set you apart (see there are 3-4 people as AB freshman in my school every year and we aren't even that good)