Return head is a know quantity from the filter pressure, ~49' of head. The only unknown is the suction head but as I posted before, that should be minimal because of the dual suction lines. I wouldn't expect more than a couple feet of head IF both lines are kept open all the time. If you want confirmation, I would need more details on the suction lines (diameters, lengths), number suction side valves, and the height of the pump above the pool water level. I can pretty guess the rest and get within 5%.