Maximum Friend Request Interval?

I have a facebook account for which I collecting friends. Every friend is targeted according to nationality and location. I scrape the IDs via Facebook Friend Bomber from groups, events and pages. I have hundreds of IDs, but I would like to run FFB all the time and be constantly adding friends instead of adding a couple and then getting the warning that I what I am doing may be considered abusive and blah blah blah... Does anybody know the best time interval to use between friends requests?

If its possible I would like to try out your program too.

Cheers

Hit me up with a PM plz or maybe someone can suggest a safe set of intervals to send friend request.

The creator of FFB recommend 40 - Not sure if they mean a day.....but thats waaaay to slow for me...dont wanna risk my own account getting banned.

Thanks for any info provided