fuel plumbing

[hardhead]

I'm about to install a 6.0 truck motor in my son's 66 and I have a few questions. Can I just plug the fuel rail return and run only a supply line with a vette fiter/reg ? If I can do this, what will I need ? supply hose from tank to a pre filter, pump, and the vette regulator with return to the tank ? Is rubber ok as long as it is upsteam of the pump ? Where is the best place to buy high pressure hose for downstream of the pump ? I have some free 1/2" SS tubing I am planning on using for the hard line.

[ls1nova71]

You CANNOT plug the return line. If your rail has a return then you need to run it back to the tank. 1/2 inch line is overkill and its harder to hook up to a 3/8 rail. I would try to keep the rubber hose to a minimum, but of course you'll have to use some. Auto parts stores usually sell EFI hose by the foot, you generally have to ask for it, but its cheaper than the prepackaged hose they have on the shelf.
Posted via Mobile Device

[BR3W CITY]

rubber is useable, but it needs to be fuel injection line, with fuel injection clamps. The other stuff can blow apart/split/bulge. High pressure fuel line is available at auto parts stores, but running braided or the "race hose" fabric/rubber coated stuff is desireable. If yo u plan on running at an NHRA track, you can fail tech for having over (i think) 12" of rubber line.

[wyomech]

go on goggle and search for, killing gremlins with aeromotive ,several online magazines have posted this article, I wish I would have read it before I burned up my first fuel pump and bought a junk fuel filter that I ended up throwing away

[hardhead]

After looking closer mine is the returnless fuel rail. I supose the other plastic line off the intake went to a vapor canister or something. Can I just plug off this line?

[ls1nova71]

Originally Posted by hardhead

After looking closer mine is the returnless fuel rail. I supose the other plastic line off the intake went to a vapor canister or something. Can I just plug off this line?

That line goes to the purge solenoid, just take it off and leave the solenoid and you'll be fine.
Posted via Mobile Device

[RaceAGMC]

Why can you not cap the return line? I thought this was what people were doing with the truck fuel rail running the vette filter.

[ls1nova71]

Originally Posted by RaceAGMC

Why can you not cap the return line? I thought this was what people were doing with the truck fuel rail running the vette filter.

You can't cap the return because the return type fuel rail has a regulator built into it. When you see people using Corvette fuel filter/regulators, they're using factory returnless fuel rails. Besides that, what would you cap it with? A bolt in a piece of fuel hose, or a vacuum cap? Remember you have 58psi of fuel pressure, not what you want spraying all over a hot engine compartment, and you likely wouldn't know it until it was too late.

[72gmcshorty]

use nylon fuel line. it's cheap and factory uses it

[mooseknuckles]

i just used the old return line...it was new any way and i only needed a short piece of high pressure hose to connect it to the filter/regulator..

[hardhead]

Not to start an arguement because I don't have the return line, but I did see on another site where the return line was removed. I believe there is a clamp that holds the male end of the line in the rail. They removed it from the clamp and cut a piece of solid rod/bolt and clamped it in place to eliminate it.

[BR3W CITY]

^so what regulates your FP? If you have the rail FPR, and a 'vette regulator...i think it could create an interesting issue should one decide to argue with the other.

[hardhead]

I don't know what pressure the truck rail regulator is set at but if the vette reg is a higher pressure, which I believe it is, the vette reg would set pressure from the pump and return excess fuel and the one on the rail might knock it down a bit more but no return. This is just guessing. I have read of it being done but I don't recall the rail reg being removed or disabled.

[mooseknuckles]

I think they have taken a "return" system and made it "returnless", not actually removing the return line completely...

[OneOffStroker]

I had a return rail on my 5.3 but didn't want to run a return line all the way back. I bought a returnless rail and swapped them out. It was fairly inexpensive.

The returnless rail is nicer in my opinion, as it is all steel, as opposed to the mostly plastic design of the regular one. I believe it came off of a FlexFuel 5.3, in case you are wondering.
However, there was drama attached. Something about the FlexFuel intake/injector combo is different than the regular one. I had to modify the mounting tabs a little bit to attach the new rail to my older manifold. Easy fix, and I was glad to do it over running a return line from the engine to the tank of my Burb.

[FMCustomz]

Oneoffstroker, Did you run flex fuel rail and injectors or just the rail? will the stock injectors fit in the flex fuel rail? Im looking at swaping to a returnless fuel system.

[OneOffStroker]

@FMCustomz - I used the stock injectors in the FlexFuel rail. They fit fine, but as I mentioned earlier, there was a discrepancy in overall fitment. I believe the FlexFuel injectors are longer than the gas ones, so the mounting tabs on the new rail were lowered to compensate for that. I cut some pie shapes out of them so they fit down around the tabs on the mainfold, and then secured them with fender washers over the remaining part of the rail's tabs. It sounds weird, but turned out pretty slick and fully functional. I don't have pics, but I could shoot some and post them if you need further detail. That would take a few days though, I'm a busy guy. Oh, and get new o-rings for the injectors. It's only a few bucks for the set of 8 rings, and I'm sure you'll need them.