If you have an engine that is in need of more fuel,and you are running a base pressure of 42 lbs. and have reached the end of your pump's ability to supply enough fuel,with your current injectors,to maintain the proper A/F ratio,it does you no good to buy bigger injectors. The thing you must first do is create the ability to move more fuel to the engine. The 3 ways to accomplish this is to send more voltage to the current pump or buy a bigger pump or a second pump. Once you do any of these things,you can raise the base pressure which will flow more fuel through the same injectors. Again,the first thing you must do is move more fuel.