Hmm.. 40 words over might be okay but 140 is a bit too much. I'd try to follow their guidelines. Word limits are word limits. It's not worth getting on Admission's bad side because of this.
u can search wharton q & a in adcom blog. one post related to this issue. 1) if you had,say, 50 words more than the limit, how abt over 60 words or 70 words? Then, where is tolerable cut-off? 2) Should articulate your idea within limit. they think concise expression is basic.
But they will not physically count the no of words.