READ MORE ABOUT FUEL INJECTOR SIZING BY CLICKING THIS LINK HERE!

This tool will help you size injectors for your build:

 

This tool will help you determine flow rate changes in relation to fuel system pressure changes. Far too many websites provide absolutely wrong calculators that have literally, absolutely (without exaggeration) 0 relation to the real world. This calculator is as close to real-world results as is necessary to provide base figures for injector choices and tuning.