OneJSupra;1162265 said:
I want to get close to 500 maybe 480rwhp with the 540cc around 19-20 psi of boost. Or is that running too close duty cycle with these injectors? How do you calculate these things?
It's easy. to calculate. 540cc injectors will flow 540 cubic centimetres (AKA, mL) of fuel per minute. Your motor has 6 of them. 6x540cc/min * 60min/hr = 194,400 mL/h
194,400mL/h / 1000mL/L = 194.4 L/hr
A good rule of thumb is never run your injectors past 85% duty cycle.
194.4 L/h * 0.85 = 165 L/hr
Now, most Denso injectors run around 38psi of static fuel pressure. YUour fuel pressure is a 1:1 ratio FPR, so fuel perssure will raise 1psi for each psi of boost. If you're running 20psi of boost, fuel pressure will be 58psi. There is a small pressure drop due to the restriction of the lines them selves, 5psi is a good estimation. Less if you have larger lines. That gives you 63psi of fuel pressure.
It's then a simple task of finding a flow chart for your fuel pump, and seeing if it can supply enough fuel. This will only tell you if you're pump is up to supplying the injectors though. Trying to figure out if the injectors can supply the power you want is a whole different story. In general, for most 6 cylinder motors, I like to use 1cc=1whp. So, 500whp would need 500cc injectors. That's only a general rule of thumb though.