even then, you're much better of NOT taking any sub till you feel like shit (and there is a good chance you won't feel that bad after such little use).
a couple days of two or three bag a day, even with some real fire, wouldn't necessitate any suboxone. especially in my own experience according to my own brain and body chemistry. again, I know of other who might feel otherwise though.
but if you were gonna take suboxone under such circumstance you don't need more than 2mg. practically speaking no more than four for sure. you've got no business taking a full eight in any such case regardless.