SPRINKLER TALK FORUM - You Got Questions, We've Got Answers

I have a pressure problem with my system. It has always been a problem. I installed the system when my house was being built. I have 8 zones with any where from 3 to 12 heads on each zone. I have city water with approx 42 psi. I have to manually turn off some heads to get the system to work. I need help to know how to correct this problem without tearing out the whole system. Can I add a booster pump? If so how do I calculate what size pump I need?
Thanks

I have 7 gpm at the hose bib. Pressure drops to 32-35 psi with 1 zone of sprinklers on. Measures about 42-45 psi with no water on. I have 3/4" copper into the backflow valve and 1" pvc going to the zone valves.

What will check valves in the risers before the heads do? How do I determine the nozzle size?

I have a variety of sprinklers, but the biggest problem is where I have 3 rainbird t series with 1.3 nozzles. I have to turn 1 off and the other 2 barely work. I also have a zone with 8 adjustable pop ups set at 1/2 pattern. They are 1.12 gpm each. They also don't work very well. I would like to add a booster pump for this and also because my outside hose bib I use for washing cars doesn't have enough pressure to satisfy me. I don't see booster pumps on the website. Are there any? If not, I have access to Teel pumps, but I don't know which size I need. Also can I add a pressure regulator after the booster pump to keep the pressure constant while running a variety of sprinklers and hoses? What do you use to make a booster pump cycle on and off?
Thanks for all the help.