Adjusting output flow on pressure balance valve

I just had a new Wolverine pressure balance valve installed in my shower. The valve feeds two faucets. One faucet feeds the overhead shower head and the other feeds the side shower heads. When both faucets are open, the overhead shwoer head stops working and the water is divereted to the side shower heads. Is there an adjustment on the mixing valve that will allow water to flow to both the overhead shower head and the side shower head?

valve

No. The legally allowed maximum flow may be controlled by the shower valve rather than devices in the heads. If that is the case, NOTHING will increase the flow.