As far as I've seen, it seems like Torbjorn's turret doesn't need to placed in a specific direction like TF2 and Dirty Bomb, so that's not an issue.
What I'd like to know is if it has a cutoff range, or does all it need is line of sight?
Meaning, could I place it on a high position that's far up, such as on Hollywood 1st obj elevator, and still have it shoot players that are coming out from under tunnel?