Stupid question on fuel pressure regulator

[Adam78]

Does the direction of flow through the regulator matter? I ask because I have a aftermarket fuel rail (bar stock style) with an aeromotive FPR and I am going to replace the fuel lines as well as put the stock regulator back (I'm hunting for a leak). Of course, I'll have to mount it somewhere since I don't have the original fuel rail and therefore I can't remember which way is the inlet and outlet for the regulator. Thanks :-)

[zKars]

yes it matters.

And don't use two regulators. Use the stock regulator only in its after-the-rail stock position. At least that's my advice if you are keeping the fuel pressue at stock levels. The FSM for the 75-78 will show you a picture that shows which tubes are in and which are out.

[Zed Head]

 (I'm hunting for a leak).

If you mean pressure leak-down, not external leak, the Aeromotive regulators all do that.  They're not designed to hold pressure, only to regulate it during flow.  Actually, from what I've read, pretty much all of the relatively inexpensive aluminum body adjustable regulators leak-down quickly.

 

There are drawings on the last pages of the Engine Fuel chapter that show the plumbing of the factory FPR.

[siteunseen]

If you have the '78 fpr it has one inlet. The smaller tube on the bottom is the return line. That's the only style I could figure out how to work with my aluminium fuel rail. I teed it off the back end closet to the windshield.

[Adam78]

Yeah, I meant a leak-down although I can smell just the slightest amount of fuel in the engine bay when the system is pressurized. It has aircraft fittings, a Russell filter and the aeromotive FPR. I've read the threads that mention the leak down tendency of the aftermarket FPR's and thought "screw this, I'm putting things back to stock", although I will keep the aftermarket fuel rail. I got a roll of EFI hose, a new OEM FPR and filter and had to get on EBAY for the filter bracket. I'm just going to put NPT-to-BARB fittings on both ends of the rail and maybe bolt the FPR to the firewall or something. The lines connecting the pump to the tank and hard lines are new.

[siteunseen]

I've got mine where the heater hoses go through the firewall, zip tied.

You'll need a long piece of vacuum line too.

Edited October 9, 2015 by siteunseen

[siteunseen]

I couldn't remember why I had a "T" on that end, I'd forgotten about the cold start valve. 

 

 

And this is all I could find for a thread sealant for brass into aluminum.

Edited October 10, 2015 by siteunseen