I'm no James Hunt but imho the only thing my M2 needed for track day was the BMW track pads & plenty of extra fuel. The limiting factor is almost always the driver. Resist buying mods & spend the money on track time and tuition.
I drove to the track with the road pads & when I got there jacked it up and swapped em out for the track pads. At the end of the day we swapped em back and drove home
I got just under 100 miles from a full tank. Did I say take extra fuel?
Depending how hard you are on the car then maybe some new tyres after but I had plenty of life left for some more road miles. I'll probably invest in a second set of stock alloys as race rims with the personal favourite 888s tyres.