It will as long as your inflow to the overflow box can keep up. That's where balancing it will come into effect more. If you put too big of a outflow pipe on you will see the water pull into the overflow box and then immediately drain down to the sump, the inflow to the overflow will need to be increased then or the outflow dialed back via valve, which is how it is now to my understanding. Increase the flow into the overflow and see how is does with the ball valve wide open.