It's all covered in my build.
I have two nozzles. One is 1.0 gph starting at 4 lbs boost and a second one at 2.0 gph starting at 8-9 lbs boost.
I cranked my pump up to 120 lbs. pressure. It does cycle on and off but the new internal bypass pumps are really the way to go so you don''t have pulsing.
The higher the pressure the finer the mist....the finer the mist the better it cools the air.
Is mine ideal???? ....probably not but it has worked quite well for 4 or five years.
I use quite a bit of water and I can't remember the exact flow rates in cc's per minute. I use the calculator on the Devils Own website and for the hp I'm putting out I'm pretty close to what they say I should be at.
I did convert the flow rates from gph to cc's/min but again I can't recall exactly what they were....I also tested the flow and it was higher than what the nozzles were rated at and Devil's Own said that was because I run lower pressure than what they test them at. They test at 200 psi and say they flow less the higher the pressure.
I stage mine because 2.0 gph at 4-6 lbs boost made my engine blubber and cough on the mountain passes when I was running the insta-boost turbo.
With the 1.0 gph kicking on at 4 lbs it doesn't mind that amount and also I have two switches on the dash that I can cut boost control and WI and still get 6.0 lbs boost without needing the water.
The intercooler has changed all this now since my air temps are staying below 107 degree at 24 lbs. boost.
It's going to climb a little when the weather gets hotter but I think it will be fine.