I'm brain storming ways to plumb for my EFI build. Up until now, I have always assumed that the fuel pressure regulator went after the fuel rails (for MPFI). But according to AeroFlow, their regulator can go before OR after the fuel rails. I've attached the regulator instructions. This means I can use a "T" fitting and feed my rails from the rear. Then I could plug the front end of the fuel rails. That would save me a lot of plumbing and fittings. Anyone had experience with this?
Just wondering why not leave the stock efi fuel rails as they were from ford? Works for all my efi's, You need a supply line AND a return line anyway, run two lines from the tank to the front and hook em to the stock fuel rails. Done.
According to Tanks Inc, you can do it this way. But instead of plumbing the rails in series, I would put a "Y" block after the regulator and feed them in parallel.
That's sort of how the newer returnless systems are plumbed, difference is there is no regulator... Always was a bit uncomfortable the second fuel rail could be starved so to speak, but the engineers no doubt know what they were doing... My supercharged Marauder ran 42Lb injectors without issue...
For those returnless systems, the PCM & FPDM(fuel pump driver module) communicate to determine what the fuel pressure should be dependent on engine load... Also a electronic sensor on the fuel rail that PCM uses to determine current fuel pressure, FPDM then varies voltage to pump motor to increase/decrease pressure...
Well, my current plan does not involve any of those return less components. Just a Tanks Inc in tank pump, filter and EFI return style pressure regulator.
Rusty, I'm using the Tanks Inc pump. I did rails like figure 1.2. http://aeromotiveinc.com/wp-content/uploads/2014/09/131-0109-0revH.pdf Micah
i have been putting together systems lately with the regulator in the back by the fuel tank with just a feed up to the fuel rails. the big difference here is the fuel pressure does not change for manifold vacuum. the most modern fuel injection computers dont have problem with this. the older factory fuel injection computers need this.
I'm liking this method. Any problems with pressure fluctuations? I'm planning on a 255lph pump, a good quality regulator, running 43.5 psi with a MS3extra. Not sure if that ecm can do a constant fuel pressure. What do you think, Bryant?
Well if a vacuum reference is needed for the regulator one could always run a steel line back to tank similar to the line for trans modulator... If you aren't using the factory tank vent line, use that...
