Pats have scored 37+ in 5 of the last 6 games:
43-17 vs. Cincinnati (highly rated defense at the time)
37-22 @ Buffalo (above average defense)
27-25 vs. NY Jets (top run defense; only 20 minutes TOP)
51-23 vs. Chicago
43-21 vs. Denver (above average defense)
42-20 @ Indy
Detroit hasn't given up more than 23 points in a game, but they also haven't faced a lot of top offenses (they caught GB early, when the offense was struggling, and NO hasn't been firing on all cylinders so far this season; both of those were home games for the Lions). They gave up 21 points in the 1st half against Atlanta.
I'm guessing around 24 scored by the offense, plus 7 more by the defense or ST.