OK you can assume that this is his continuing range to your turn bet: KK+, JJ, 88, 66, AKs, KJs, AKo, KJ. For simplicity assume he never c/r any of this, but just calls. You already calculated your equity E against this range. You know the pot size P and the bet size B. You are trying to find which folding frequency F you need for the EV of all the outcomes to be greater than 0.

Refer to part #13 of http://www.flopturnriver.com/pokerfo...ad-180192.html

Pretty much all you have to do is plug in all the numbers in that equation: set EV=0, plug in all the other numbers and find F.