Holley EFI

[allrightmike]

Question is, woild it be advantages to place the pressure regulator as close to the injector unit as is practical? My thinking is, placing the regulator toward the back (near the tank) would not compensate for a pressure drop at the injector unit. To be clear, the regulator is down stream (return side) from the injector body.

[RustyCrankshaft]

Doesn't really matter. If the regulator is mounted in the back then I'd put a gauge at the TBI/fuel rails on initial set up so you can adjust for the pressure drop. Once you figure out what the pressure drop is you just run that amount of off set.

What Holley EFI are you going with? Some of the TBI's have the regulator built into the TB.

[allrightmike]

Sniper Stealth-external regulator

[62Falcon390]

most regulators need an engine vacuum reference

[allrightmike]

Need to check the regulator for vacuum port.

[Russ67Scode]

Holley makes a drop in pump/fuel level pickup in the tank for FORDs  has a built in regulator these are good for approx 600 hp. Many people with a non stock cam have little difference between idle vac and wide open throttle. Boosted applications definitely need a reference line to a regulator
We have a setup on a friends 70 mustang with a good running 351W  he absolutely loves it