Corvette Regulator with a stock 5.3 return line Fuel rail
 

Okay yall, so I messed up. Help me figure out the overall best move here:

I bought a Tanks, Inc tank over the phone and they were like "You want the fuel install kit" and I said yes... but only later.. AFTER cutting lines, installing fittings, installing the Vette Regulator/filter.. did I see its for returnless rails only.

What I need to choose between:


Approach 1: Keep the return style rails, and:

Ditch the vette regulator and buy a filter instead: $30 for the filter, will probably resell the vette regulator and make $20? net $10

Buy 10 more feel of Russell Twist Lok fuel line - $50

Buy an AN-6 male-to male adapter, another twist Lok fitting, and another QC for the return rail to extend the return line I've already cut to length (makes the tank easier to remove anyways) - $30

I've spent $90 extra, I have a frame mounted filter, and I have a return line, which the engine is designed for and I assume the PCM is expecting.


Approach 2: Swap out the return style rail for a returnless rail

Cost:? will a later year 5.3 returnless line work okay? Will it even fit? Are the injector plugs different? Are the injectors different? Will the PCM be displeased?

I've seen anywhere from "Ditch the vette piece, run a return line/Just plug the return, its fiiiiiine (no)/Buy a returnless billet piece from eBay/ etc"

The $90 and be done with the research option looks good, but if I can swap the rails with no drama, that might be cheaper and better!

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

So my .02 and I may be all wet. If can find a good way to plug the return side of the fuel rail that seems like a good way and least expensive way to go. If you use the C5 FPR and use it's return port back to the tank the fuel rail will only see 58 psi. The PCM has no clue what the fuel pressure is and doesn't care as long it's 58 psi.
Not knowing the year of you 5.3 I think the injectors stay the same for a number of years but after 2006? the injectors changed because the electrical connectors changed and the length of the injectors?
Check with the folks over on LS1tech. I'm sure they can help.

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

That's exactly what I did..plug the return fitting on the rail...I used a pushlok to -an...then a -an cap on that..I stuck with the vett filter/reg..been holding for over 20,000 miles with no issues

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

True, to an extent, however, the fuel maps are different between a set 58psi and a vacuum regulated 58psi. so you need to adjust for it in the tune for it to be right. That said, the vacuum regulated return style is actually a better system, but the corvette set 58psi is just a little simpler. If you already have a return rail, i would just run it that way and use the cheaper filter. If you insist on going returnless. do yourself a favor and just grab a returnless set of rails from the junkyard and skip trying to plug off the return line. I know people do it, but its just a potential spot for trouble in my opinion.

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

20,000 miles ain't bad... I could definitely just get a $5 cap and see how it runs I guess. It wouldn't be a considerable effort to run a return line after the fact if that fails. I probably wont even drive this truck 20,000 miles in 5-10 years.

I have a 2003 5.3. I've seen posts on LS1Tech and havent found anything definitive about fitment, although I've seen some folks saying they swapped out for returnless rails and had to make custom brackets and such.

LS1Nova, I applaud your consistency, I found a post from 2012 where you recommended running a return, both here and on LS1Tech!

I couldn't find anything definitive saying what rails will fit... flexfuel rails apparently will, but then i need to deal with new longer injectors, and TBSS rails were mentioned but they cost more than $90. Pick n pulls out here are picked and pulled before I get there, so it looks like I try the $5 cap. If it sucks eggs, I do the $90 return line.

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

Returnlrss rails will fit as long as they come from another truck engine. The injectors are different from flex and non flex and return style rails are flex and non flex specific. If you're going to go the returnless route, those rails are cheap, but I guess if you can't find any in the yards around you that makes it a little more difficult, however, keep in mind, if the plug you cap the rails with fails, it will likely leak fuel on a hot engine. Also, you need to remove and plug the regulator, when those fail they leak fuel too, only you generally don't notice it because the vacuum hose sucks it into the intake, but it you do notice it running bad.

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

I used ls1nova's advice on the fuel rails for my build. I went with returnless rails from another truck engine. They fit right in and got rid of the regulator on the rail. Great advice and easy to do.

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

If I can find a reasonably priced set, I will probably take that approach... cant have fuel leaking out!

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

I simply ran a -6 return line to the tank from the intake fuel regulator like it was designed. Hard lines would have been cheaper

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

Agreed! Simpler and cleaner in my opinion

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

well I am in the same boat with my current build. I have a 2013 return type engine and I have just installed a "corvette style" filter/regulator. I am wondering as opposed to re-doing my setup, can I just run the engine return line and "tee" it into the return line side at the filter/regulator? also if I understand right then my return lines can be the F.I. hose with F.I. hose clamps ("Tee clamps) and can just be clamped over the steel line nipples?

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

My C30 is also a return rail, and i run a vett reg/filter..what I did was use a qd to -an on the return fitting on the rails..and then put a -an cap on it..
I know it's not the preferred method , but it works..being working for over 10yrs and 20k miles now..
No need to tee them together..
You could also swap to a returnless rail..

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

mongo, thanks for the reply, as above if I understand then I can just cap that line off at the engine rail?

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

Yes...but be sure to use the push lock to -an , and a -an cap...

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

mongo, 10-4.. I was thinking the same, thanks again!!!

just curious though... I guess in doing the "cap" proceedure does not add any additional "pressure/back pressure" inside the fuel rail/engine system???

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

I've had no issues...Ive got a gauge on my fuel rail and I havnt seen anything excessive..the vett reg takes care of it..

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

here you go rodstored
this is what i used...or similar under a diff name

https://www.summitracing.com/parts/rus-640863

https://www.summitracing.com/parts/sum-220640b

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

Wow. There are so many ways to skin a cat.

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

Mongo, thank you!:metal: I appreciate the reply. that is exactly what I was thinking you did. I will order/get those fittings and do the same thing. I took the line off from the engine side last night as well as removed the steel line from underside :ito:. man! the first clamp was a PITA to "open" to remove the line...:mad:

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

Just quick note the fuel rail fitting that Mongo used has been updated to include a retaining nut so the the fuel rail fitting cannot come off the fuel rail by accident.
Note to Mongo. I know you haven't had any issues but I would safety wire that fuel rail fitting can't back off if the plastic retainer fails.

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

Were the pushlocks coming loose?...with the millions of them that were used, I've not heard of any issues with them coming loose....not saying they wont...anything can fail...and it would be a bad day if it did..

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

hhmmm... interesting, I was trying to use a fragola "quick connect" fitting on the factory return line (at engine) & it would not "connect", it seemed like the fitting housing was too long for it to "lock" onto the factory rail line - rail line was a shorter "nipple" than the fitting?? so I am just using the factory fitting (with plastic tube) and hose fitting back to the cap. :confused:

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

well I did what Mongo indicated, I capped off the return line at the engine side. I did use a portion of the factory line. I cut the plastic and added a hose (fitting) at end with a cap.

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

Can you post a pic of this? I try and not comment on this any more because of conflicting ideas, but what you say you have done doesn't sound super safe, at least the way you worded it.

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

I'm with Eric...something dont sound right about that...
You shouldnt have any plastic line..the pushlock snaps onto ths metal return rail..the cap goes on the -an pushlock

Nothing against Eric, absolutely nothing,,,,nothing but respect..hes helped many a member thru alot of issues
but I know he doesnt like the way I did mine..but I did mine way before I ever found the 67-72 site..what I did was recommended by a LS swap guy...its been holding for yrs and miles..
The way he would recommend, I'm sure , is to swap to a returnless rail,, which I might have done back in the day if I'd known it was a option..but I just didnt know back then..

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

all, I will get a pic tonight & try to post . I appreciate the responses & I am only wanting the thread to be helpful (to me ofcourse) but also to others who don't have knowledge (as myself) of how to handle a similar situation. As in many problems there can be multiple solutions & opinions. ;) Obviously the safety aspect is highest priority and hopefully that solution isn't too expensive.:ito:

thank you guys for the information and support :metal:

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

First off, Mongo, you're right, I'm not a fan of blocking off the return, but glad there's no hard feelings about it. This is why I said I refrain from mentioning it. That said, in recent times there have been parts made to make it safer. One of my pet peeves about it is the known fact that when the regulators fail, they leak past the diaphragm, which without a vacuum hose sucking it back into the intake, will allow gas to just run all over the intake. At a bare minimum, I would get rid of that for peace of mind. ICT Billet now makes a block off for it, and for $20 and about a half hour of time, would be well worth the insurance. https://www.amazon.com/ICT-Billet-Re.../dp/B084KN6CHH

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

Thanks Eric...I didnt know about the ICT piece either...I'll def look into it..
And man naw...no hard feelings at all...I see you helping a lot of folks with all kinds of issues...
gotta respect that you take time to do so..

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

ok guys... here are the pics. one is it attached using the factory "quick connect" fitting - and the "plastic" line molded on. another pic is with the assy. disconnected & sitting on floor. lastly a pic of the end that has the hose fitting and cap. please feel free to voice thoughts. I want to reiterate that this setup is for a 2013 4.8 truck engine with 57K miles. I guess I don't know what the solution is to handle the return line at the engine?
ls1nova - i looked at the link, but confused on "how" it works and purpose? in some of the reviews it was indicated that this was not a block off plate? also it is recommended for up to 2003 engines?
finally as I indicated previously, that when I tried to use a "aftermarket" (fragola) fitting the "clamping"? portion of the fitting was too long and would not fit on the engine return line - hence the re-use of the factory line.

I REALLY appreciate the responses from you guys & I apologize for my lack of terms & knowledge. you both (the board in general) are very patient :metal:

THANK YOU:metal:

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

I forgot to mention that the end of the line points down to the ground just incase a leak occurs. obviously i want to do the "correct -safe" solution...;)

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

I'm not sure about that....it "might" be ok...and it might not...
as for it pointing at the ground , think about where the exhaust is, and fuel spraying around ....if it should fail
If you have the correct pushlock, it will snap right onto the rail...did you have the correct size?...
I havnt looked at Eric's link yet so I'm not sure what involved there..
You can always change the fuel rail to a returnless rail...junk yards are full of them...

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

So your engine is a 2013? If that's the case, you don't have a return, so you also don't have the regulator on the rail. Hard to tell from your pics, but it looks like you have a metal fuel rail, so, I think what you are seeing is the purge solenoid line. I know for a fact that the purge solenoid line is what you capped off, and it is in NO WAY capable of holding fuel pressure, but it appears you don't need it anyway.

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

Mongo, yea I see your point... I was thinking along the lines of the fuel leaking onto the engine. I am not really wanting to change the rail, although if that is the common sense/practical solution then I can attempt that.

"So your engine is a 2013? If that's the case, you don't have a return, so you also don't have the regulator on the rail. Hard to tell from your pics, but it looks like you have a metal fuel rail yes I do), so, I think what you are seeing is the purge solenoid line. I know for a fact that the purge solenoid line is what you capped off, and it is in NO WAY capable of holding fuel pressure, but it appears you don't need it anyway."

nova, I guess I am still not understanding? I apologize.... so what should I do (your recommendation) with the line :confused:? originally it ran next to the fuel feed down to the frame side and then not sure. when I got the engine both lines were cut right after they turned into the braided line material - next to the transmission. I assumed that it was a return line... but????

again I thank you guys for your patience with me.:metal:

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

Ahhhh...2013....
What Eric's saying is if you have a 2013, there is no return rail...probably why you couldn't get the quiklock to work

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

ok guys I did a little investigating now that I know what that is. so!.. if I understand right then could that line be connected to the '86 charcoal vapor canister? if not then just put a vacum cap over the line/engine outlet? ... am I understanding right? :ito:

thanks again!!

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

You could potentially hook it to your charcoal cannister, but without the wiring going to it, it would never open. Most people just remove it and put a vacuum cap on it.

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

"..... but without the wiring going to it, it would never open"
what wiring are you referring to? my engine is a complete drop out & included all wiring. the valve is OG to the engine & is stock. sorry for not understanding...:waah:

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

I figured you had an aftermarket harness or had modified the factory one and it was removed because it isn't needed for the engine to run. The wiring for it will be in the factory harness, but without the fuel tank pressure sensor I'm not sure it will ever get the signal from the PCM to open. The PCM runs a diagnostic on it at certain times to make sure there are no leaks in the EVAP system, and it's what controls the purge solenoid. Some people say it will work without the tank sensor, but I've never tried it.

Re: Corvette Regulator with a stock 5.3 return line Fuel rail
 

nova, thank you, 10-4 on the info. i will just cap off the line and keep it hidden under the factory engine cover.

in general, all I really appreciate the replies & information. hopefully this will help someone else down the road as well.