IDK, sounds like you should decide if its worth trying. But a new Infraction 3S motor only costs 40$ on Jennys RC.
(edit) NVM, the Interaction motor costs 50$ (3900KV) the normal motor (3200KV) costs much less...
I'm Actually wanting to do the same with my Vendetta. 4S with 3900KV would be fine for speed runs. But bashing would be quite hard on it (Takeoffs and such)