It's been a year since my last JFK transit on delta, IST-JFK-CVG. I had about the same times for the connection. I just got to the JFK-CVG before it began boarding, but then found out that Delta was holding the plane for connecting passengers. The porter at the international arrival (where you put your luggage back on the rack after going through customs) told me it would be shorter timewise to go outside the building and reenter through security (lines were short). Best of luck. (just looked and noticed that your flight is El Al not delta, that being the case I don't think you would want to chance the tight connection since you will have to transfer from terminal 4 to either terminal 2 or 3 on delta) (You may want to post to the delta board for more advice)