1badFB

iTrader: (1)

In preparation of tuning my new engine, a simple question crossed my mind. Why is it that we still use boost referenced fuel pressure regulators?
Obviously the simple answer is differential pressure, and perhaps that older fuel injectors had a lower overall pressure limit. Maybe the older, basic ECUs would not properly correct for the differential pressure change?

Now that most of the current injector options support much higher fuel pressures, and ECUs have come a long way: is there a reason not to run a higher pressure set statically for better atomization outside of high boost?
Example: if my target boost is 30psi, why shouldn't I just run ~75psi static so there is always a minimum of 45psi differential. Any reason not to do this on a modern ECU like a Haltech Elite?


In my mind there are advantages and disadvantages but the system would be simpler with less failure points. Just interested to hear some opinions!


Thanks,
Alex

j9fd3s

iTrader: (3)

i think there are some early returnless fuel system cars that are like this. i think the 99-00 miata is like this, it has a regulator, but its in the tank and not boost referenced.

the other thing that might be interesting is how i think the Ford setup works, they have a fuel pressure sensor, and a variable controller, so they run the fuel pump up to the target pressure, and i guess you could map that

Slides

It makes fuel calculations easier with referenced reg. Some other things to consider, fuel pump power consumption, noise and heat generation, minimum effective fuel delivery from injectors sized for big power, injector/pump function while cranking with weak battery.