Does anyone apply chemicals with a 10 GPM+ pressure washer? I have two 5.1 GPM machines that I have tied together to 10.2 GPM but I cant apply chemicals. I have the chemical injectors located just prior to joining the machines. When I run the machines separately the chemical injectors work great but when I run them together they don’t pull chemical. I even tried putting a 2.3 injector at the hose reel about 10′ away but still couldn’t pull chemical.

Is there a larger orifice injector?
Other solutions?