I've done some searching the past couple weeks about fuel return setups and after seeing what AZDave, Terry and others have done with their fuel lines, I'm interested in tackling this project in the future. So, from what I've gathered here on the board this is what I've come up with. I decided to draw a layout this morning of what I think the setup will consist of...to the best of my knowledge from searching etc...don't make fun of my artistic abilities now heh.



Here are a couple issues I'm not completely clear on and may need some guidance. The fuel rail would be a custom one like Mr.Blunt2gnt has setup, and that is if he would be willing to have another one made :)

First being the stock hardline that feeds to the fuel rail...I believe its a 5/16" fitting...how many of you guys utilized the stock hose from there? I've seen some guys cut off the end and clamp a fitting on, but I was thinking of using some type of adaptor (not sure which size) that would allow me to run 6AN SS hose off that stock 5/16" to the FPR and so forth. Just need to clarify type of fitting/size here.

Second being, I've seen some guys use a T to split off and run a FP gauge...I saw Earls has a In-line FP guage adaptor...has anyone used one of these? I'm assuming it would be okay to run as long as I have the right fitting to connect the gauge up. I think this would be ideal rather than using a T with male ends and having to use additional 6AN hose end fittings.

The only other thing that I lack experience with is using a double flare tool. I think I'll need this for the 3/8" return and where it'll splice halfway between the rail and FP access cover.

This is definately a costly fuel setup, but I want something that others have tried, tested, and have had positive results with. Thanks guys.





http://www.dsmregistry.com/detail.php?carid=1185

I guess I must have drawn this up right, because I was sure someone would have said somethings not right by now. If someone could clear up a couple of the issues I have above, I'd greatly appreciate it. Thanks.


http://www.dsmregistry.com/detail.php?carid=1185

Look, I was thinking what you were. Problem is, even with that 6AN line, it will only flow what that 5/16 line will allow it to. So You could use 4an.

It would be better to use the 3/8 for the feed and the stock for return.

In the end, haveing the rail that supports 6an, and all the adapters for the stock line and the fittings. I Added the totals, having a makeshift system with the stock lines vs an all 6AN system, it was a diff of less then 100 bucks. If you are going to use 6AN fittings, just do the whole thing.

Now if you will use AZ daves method, with stock lines, parts etc, It IS way cheaper.

Alright, seems there are contradicting ideas on how to run an FPR, there's this way;


http://www.2gnt.com/nuke/modules.php?name=Sections&op=viewarticle&artid=82

and then there's this way;

http://www.2gnt.com/nuke/modules.php?name=Sections&op=viewarticle&artid=59

which one is the way? I always thought it should go tank/filter/rail/guage/FPR/return Like the first one, so that the FPR held pressure in the rail and the injectors wouldn't pulse the pressure out. I thought the other way was reserved for carburated setups. Oh well, it probably works both ways and is just there to confuse us all :shrug

Originally posted by Keith2172
Alright, seems there are contradicting ideas on how to run an FPR, there's this way; http://www.2gnt.com/nuke/modules.php?name=Sections&op=viewarticle&artid=82 and then there's this way; http://www.2gnt.com/nuke/modules.php?name=Sections&op=viewarticle&artid=59 which one is the way? I always thought it should go tank/filter/rail/guage/FPR/return Like the first one, so that the FPR held pressure in the rail and the injectors wouldn't pulse the pressure out. I thought the other way was reserved for carburated setups. Oh well, it probably works both ways and is just there to confuse us all :shrug

they both look that same to me...

now if yoru talking about xcansbox's(did i get that name right?) drawing ? Yes the FPR is on the wrong side for his. The regulator does just that, regulates. In a sense it is like a "pinch" in your line to raise or lower the pressure. It does this in ref. to the vacum or boost.

One thing though, I would ditch the stock filter. I think theres articles about it showing very poor flow. With the K&N ones costing only 20 bucks, why not?

Hell I even thought about keeping it a "returnless" system. Problem with that is that the regulator would be in an weird location and the vac/ ref signal line would be too long.

Originally posted by Chamuko

Originally posted by Keith2172 Alright, seems there are contradicting ideas on how to run an FPR, there's this way; http://www.2gnt.com/nuke/modules.php?name=Sections&op=viewarticle&artid=82 and then there's this way; http://www.2gnt.com/nuke/modules.php?name=Sections&op=viewarticle&artid=59 which one is the way? I always thought it should go tank/filter/rail/guage/FPR/return Like the first one, so that the FPR held pressure in the rail and the injectors wouldn't pulse the pressure out. I thought the other way was reserved for carburated setups. Oh well, it probably works both ways and is just there to confuse us all :shrug

they both look that same to me... now if yoru talking about xcansbox's(did i get that name right?) drawing ? Yes the FPR is on the wrong side for his. The regulator does just that, regulates. In a sense it is like a "pinch" in your line to raise or lower the pressure. It does this in ref. to the vacum or boost. One thing though, I would ditch the stock filter. I think theres articles about it showing very poor flow. With the K&N ones costing only 20 bucks, why not? Hell I even thought about keeping it a "returnless" system. Problem with that is that the regulator would be in an weird location and the vac/ ref signal line would be too long.

Crap, your right! I was in a hurry and didn't read all the way through the article, what would Dino say "things you do in a hurry that'll come back to bite you in the ass later". The drawing at the top of this page is what I meant as the counter to this. So we are mostly in agreement that the FPR should be AFTER the rail then, huh?

Originally posted by Chamuko
Look, I was thinking what you were. Problem is, even with that 6AN line, it will only flow what that 5/16 line will allow it to. So You could use 4an. It would be better to use the 3/8 for the feed and the stock for return.

I see what you're saying about it only flowing what the stock feed can handle...so really the 6AN line is useless on that side. So in other words don't waste the money for 6AN line, fittings, adapters etc on the feed side...unless you plan on running 3/8 line all the way up to the firewall and basically COMPLETELY redoing the fuel lines. I think thats what you meant right?

One question though, in the future I know I will be upgrading to larger injectors and I've read that stock injectors will handle 4AN line fine, but with larger injectors people have had issues with lowering fuel pressures on 4AN line? Is this true?

Thanks again guys.


http://www.dsmregistry.com/detail.php?carid=1185

thats because you are trying to flow more volume through a small openning, that causes pressure.

Running all 3/8 line just means that you would need to add another 8 ft section of hardline to your drawing. The cost of the adpters would make up for that in the end.

OR use the stock line as the RETURN. The return only flows what is not needed. This is low flow and low pressure.

I think I'm confused now. All I want to do is add a return line to the system, add the FPR, gauge, new lines etc...why run a new line for the feed when the stock line can be utilized? The hardline that comes up in the engine bay and the hose that runs off that...I would need to cut off the end of the hose with the flange/2 holes for 8mm bolts, add the proper fittings to run the line to the FPR, then to the rail. That's my understanding of it.

Maybe its just late and my mind's tired of thinking.


http://www.dsmregistry.com/detail.php?carid=1185

Your FPR should be on the return side. On a car with decent fuel flow a return system is ideal because a returnless system has a hard time keeping a constant pressure inside the fuel rail.

The returnless system is just to keep emissions down and fuel temps down.

1 - Take their advice and ditch the stock fuel filter. Just bypass it totally w/ your new lines. I put my new one in the engine bay so that changing the element didnt involve jacking my car up. Plus i bought one thats polished so it adds some BLING :)

2 - No need for a T in the return line, the FPR most likely has -8 port on the front for a guage, or use the -6 port on the unused side for your electronic sender.

3 - I re-used the stock feed line as my new return line. Its already there and it flowed enough to feed my car last year, its overkill for a return. Its already under the car, why not use it.

4 - I can easily make more of those rails. It doesnt take but a day or so to turn it around and it comes out great. The rail has a ton of volume and i dont think theres an aftermarket rail that can touch it for the price.

Okay I think I got it figured out finally. Basically re-use the original stock feed as your NEW RETURN line. That will run to the FPR return port and then to the rail correct?

Then when you run your 3/8" or 5/16" hardline from the fuel pump then switch it to 6AN SS line in engine bay use that as your NEW FEED line.

If I bypass the stock fuel filter and mount a new one in the engine bay this is where the SS line will run to and then from there to the feed on the rail...correct? I think I was mixing the two up thats why I was confused.


http://www.dsmregistry.com/detail.php?carid=1185

you got its sir. I would use 3/8 as that is the closes to 6 -AN