What is the ias penalty for using the full Cow King Set? I'm trying to figure out how much ias my A1 merc needs for her to chuck fireballs at max speed in cow form.

She currently has 120 ias from the 30 ias set bonus 10 ias gloves, and x4 Shael'd Witchwild bow, but I could add another 40 by finding her better gloves and ias jeweling her helm and armor