Anyone know what the pistons are made of and what type in the E46 M3, The tech at BMW said all he can remember from school is that there is some kind of coating to decrease friction. I want to run 50-100hp of NOS but I dont know what this thing is made of, and how much I can run. Anyone Know for sure???

That engine is already performing at maximum capacity, a lot of e46 M3s are blowing engines at factory settings.