I had a burn of 4800 lbs/hr at 30,000 with a strong headwind.

ADDITIONAL:

With weather cleared, I burned 3800 per engine per hour at .78, EPR around 1.9.  That would be 15,200 lbs per hour total.  

Divide distance by Speed in knots (450 no wind, 400 westbound, 500 eastbound) to get hours.  Multiply hours by 15,200 (or whatever you think your total burn per hour is).  That should give you your trip fuel.  Add 15,000 lbs for contingencies and reserve (or, again, whatever you please).  That should give you how much fuel to load.