You are creating more problems - basically you are creating work for your pump. It is going to run longer now to provide the same results and wear out sooner. Retricting the flow does not change the ultimate static pressure. My unprofessional opinion. If the pressure goes too high, it is one of several reasons, none of which are controlled by restricting the input to your system. If the pressure climbs higher than it should while the pump is running, then either it is set wrong (your pressure switch is set too high), or the pressure switch is not working properly. If the pressure goes high after the pump turns off, then it is probably the cause of the water heater causing expansion. In that case, if you didn't have a storage tank, you would need to install an expansion tank. This is not needed on a pump system, as the storage tank performs that function. BUT, if you don't have enough pressure in the storage tank, then it can basically fill up with water, leaving no room for expansion, and the hot water heater can cause the pressure to rise as it heats water after being drained and filled with cold. Depending on the amount of water heated, and the amout, it could raise the pressure probably 50 pounds or more. You really need someone to look at the system, unless you are willing to listen and ask questions, rather than making changes without understanding, you will be causing more problems than you are fixing.