I got a PM asking me how I did it so I thought I would start a thread showing how I did and share the knowledge.

You will need two of these:


Two of these:


Two of these:


A regulator, I used one that is just like this but in black off of ebay:


You will also need one return line hose from the junk yard, I have not found a source for these new at this moment.

Also required will be a tubing cutter, I used this one:


And a flaring tool, I used this one:


The bends I put in mine are honestly dependent on how you want to mount it, mine has a curve to it that makes it loop easier.

You need to trim most of the line off of the fuel line kit so you have the fitting and a short piece of tubing. Then you need to slip on the flare fitting and put a flare on the raw end. The brass adapter will thread into the regulator using some teflon tape then the flared end will be threaded into this. Do this for both inlet and outlet of the regulator.

Take the return hose mounted to the frame rail and thread it into the return side of the regulator, it will tighten up to the line on the return side of the regulator. The junkyard hose will thread to the inlet of the regulator and then to the fuel line coming from the throttle body.

I made a "L" bracket and mounted it to the subframe rail to one of the corner screws on the regulator to support it instead of just letting it dangle. I still need to get a return line hose from the junkyard to finish mine up properly, for now it is making due with fuel injection rated hose with clamps.

Here is what the end result looks like, it hides under the snorkel really well.

 

Sweet. Thanks for posting this.

 

What did you end up doing with the FPR built into the throttle body?

 

Thread Starter's Last Activity: Dec 18, 2016. I don't expect you'll get a reply from him. This thread is over a decade old.

Wild Guess: Nothing, leaving the OEM-style diaphragm in danger of over-pressurization. I have no idea how much pressure they're designed to handle, although some of the newer 7.4L TBI engines were up around 30 psi. Maybe they had "special" diaphragms, maybe not.

The only advantage to this arrangement that I see is the option of vacuum-referencing the fuel pressure...which is not all that useful on TBI systems to begin with, which is why the OEM system isn't vacuum-referenced.

 

The advantage is that you can run a much bigger in tank pump if you want to add something like N2O or boost and use only one fuel system. My L05 has a gss340 style pump in the tank and I can't get tit to idle below 16psi with the factory regulator, and I'm assuming an adjustable one won't do any better since the fuel still needs to bypass through the same passages.

 

That brings us right back to:

 

I agree. You'd need to simply remove the spring from the factory FPR on the TB and then it would be out of the picture....the remote FPR would do all the work.


Vac Ref CAN be useful as a tooning aid on TBI; I used it to solve a problem and it worked great. HOWEVER, you don't need a remote mount, to accomplish this, or anything that an OEM regulator can't accomplish, so I don't "get it"...switching to a remote FPR. Waste of time and money. GM used a VRFPR on the marine application TBI engines in the late '90's into the mid '00's or so, you can buy that FPR housing/kit and put it on any automotive TBI; both 2 bbl units and the 1 bbl units. I USED ONE on a 1bbl unit on a Crossfire.

 

If you remove the spring, the diaphragm has ZERO support, and could over-extend and rupture--which then pours fuel all over the intake manifold near the distributor and coil.

So we're back to wondering how much pressure the diaphragm is good for, and whether that pressure-rating gradually reduces with age and use. As said...some of the 7.4L engines ran ~30-ish psi, but they may or may not have had extra-sturdy diaphragms.

Removing the entire lower-section of the original regulator--the spring, seat, screw, and cup-looking housing, so that it can be replaced with a simple flat plate sealed around the edges would eliminate that risk. Wouldn't be hard to fabricate, use an old diaphragm with the center cut-out as a gasket. I don't know of anyone making a ready-made solution.

I'm assuming that the remote regulator has it's own bypass plumbing. Installed ahead of the OEM regulator, you could block the OEM outlet so the modified ("gutted") OEM regulator becomes "dead-headed".

Installed behind the OEM regulator, (on the return side) you'd have to enlarge the fuel passages in the OEM casting to accommodate increased fuel volume.

 

All of that is well and good thinking. I think the diaphragm strength is a non issue....but let's say you're right that it's a risk: It simply agrees with what I said above: