Big,
More details please for those thinking of making the switch.
Flo Jet or other pump?
Needle valves on liquid &/or air or not?
Size of air and liquid tubing?
Type of foam Brush - 3 or 6 hole?
Size of hose to FB - 1/4" or 3/8"
FWIW (I will have to check) I think the pressure to my Flo Jets is set at about 50psi and air at about 15 PSI - No Needle valves.
Have you played with the pressure or is that where you set it and it worked?
Unless your ratcheting it down with needle valves seems like at those pressures your trying to put a lot of volume thru small openings and the flo jets (if that is what you are using) would be fighting the air pressure.