Thinking about injectors today. I want to be sure that I get an injector big enough for my hp aspirations, that will not be too big as well. I'm sure that there a injector size calculators out there that can help me answer this question but I'm gonna throw it out here to be extra thorough. 250 c.i. 16/18 psi 6 cyls 450 whp @ 6000 RPM.