Return line?
#1
On The Tree
Thread Starter
iTrader: (9)
Join Date: May 2007
Posts: 101
Likes: 0
Received 0 Likes
on
0 Posts
![](https://ls1tech.com/forums/images/ranks/ls1tech10year.png)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Trying to figure out how to go about doing the fuel system. As it sits, it has a return line, but I was just wondering if it is really necessary? Or can I just not use the return line and delete it?
#2
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Sort of up to you. A return style regulator generally does a better job of regulating pressure and makes the pump live longer and run more quietly. But not everyone runs them.
This link dicusses it in depth. Their numbers as far as HP rating and pump/line size are pretty conservative. I see guys on here with set ups that support more HP than their suggestion recommend.
http://www.centuryperformance.com/fu...e-spg-140.html
This link dicusses it in depth. Their numbers as far as HP rating and pump/line size are pretty conservative. I see guys on here with set ups that support more HP than their suggestion recommend.
http://www.centuryperformance.com/fu...e-spg-140.html
#6
TECH Apprentice
Join Date: Feb 2011
Location: Central Florida
Posts: 316
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
The old timers can remind us in the fuel injection generation what vapor lock was/is. A return style helps fight vapor lock - I am in the Florida heat so that is what I am running.
Trending Topics
#8
TECH Apprentice
Join Date: Feb 2011
Location: Central Florida
Posts: 316
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Years ago in south Florida a friend of mine had a Vega with a built 327, long tube headers too. That thing would get SO HOT underhood, it seemed like he opened an oven when he popped the hood.
#9
On The Tree
Thread Starter
iTrader: (9)
Join Date: May 2007
Posts: 101
Likes: 0
Received 0 Likes
on
0 Posts
![](https://ls1tech.com/forums/images/ranks/ls1tech10year.png)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
I have another question for you guys about the fuel system. I'm having a really hard time locating a good mounting position for my pump. The only place I can find that wouldn't require too much fabrication is about level or even just a hair higher than the tank itself. Everything I've read says this isn't such a good idea as these pumps are pushers and not pullers, correct me if I'm wrong.
Anyways, I've been mulling over the idea of using an EFI tank with an in tank pump. Is this possible for a carb'd application if I use a regulator up front to dial down the pressure? Also, would I be able to use the stock fuel line and return line or would I need something for the increased pressure? I'm just a little confused if the actual fuel pressure will be whatever the EFI pump puts out until it gets to the regulator and is dialed down or is this false? Totally lost on this one, not much experience rigging up fuel systems...I'd like to keep the stock tank and use the electric pump I've already got, but just worried about starving it or improper functioning due to mounting location.
Anyways, I've been mulling over the idea of using an EFI tank with an in tank pump. Is this possible for a carb'd application if I use a regulator up front to dial down the pressure? Also, would I be able to use the stock fuel line and return line or would I need something for the increased pressure? I'm just a little confused if the actual fuel pressure will be whatever the EFI pump puts out until it gets to the regulator and is dialed down or is this false? Totally lost on this one, not much experience rigging up fuel systems...I'd like to keep the stock tank and use the electric pump I've already got, but just worried about starving it or improper functioning due to mounting location.
#10
10 Second Club
iTrader: (4)
Join Date: Jan 2004
Location: Martin Mi
Posts: 1,068
Likes: 0
Received 0 Likes
on
0 Posts
![](https://ls1tech.com/forums/images/ranks/ls1tech10year.png)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
The Holley Blue pump is designed to be a pusher, but we have a Big Block Ford pickup with around 450 hp that works just fine sucking from the factory fuel tank pickup. It is also deadheaded at the regulator. I personally run a Magnafuel 300 that deadheads at the regulator BUT has a bypass at the pump that returns to the tank. You set the regulator at 6-8 psi and than set the bypass at the pump to around 15 psi IIRC. I ran the later setup in a Big Block Chevrolet that dynoed 775 HP to the Flywheel.
#11
10 Second Club
iTrader: (4)
Join Date: Jan 2004
Location: Martin Mi
Posts: 1,068
Likes: 0
Received 0 Likes
on
0 Posts
![](https://ls1tech.com/forums/images/ranks/ls1tech10year.png)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
We have used a mallory regulator to do exactally what your describing in you last paragraph. It was on a 1996 V8 S10 that had a mild 350 in it and we used the factory 4.3 in tank pump with a mallory regulator to regulate it down to 6 psi for the carb. Hope this helps. Eric L
#12
On The Tree
Thread Starter
iTrader: (9)
Join Date: May 2007
Posts: 101
Likes: 0
Received 0 Likes
on
0 Posts
![](https://ls1tech.com/forums/images/ranks/ls1tech10year.png)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
We have used a mallory regulator to do exactally what your describing in you last paragraph. It was on a 1996 V8 S10 that had a mild 350 in it and we used the factory 4.3 in tank pump with a mallory regulator to regulate it down to 6 psi for the carb. Hope this helps. Eric L
#14
TECH Apprentice
Join Date: Oct 2007
Location: Granada Hills, Ca
Posts: 385
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Mallory makes a regulator, called a 3 port return style. #4309. I had a 255in tank on my mustang and converted to a carb and used all my existing stuff. Just spliced a switch into the factory wiring, so I could turn the pump off and on whenever.
Orme Bros in Northridge, CA sells the compression fittings for the factory lines to convert it to -6 AN. Then you run -6 lines in and out of the regulator.
![](http://i10.photobucket.com/albums/a149/qwiknotch/convert/carb/carb004.jpg)
I cut the factory lines and put the fittings right on the lines... I can't the pictures of the lines with the fittings.... might be on my old hd.
![](http://i10.photobucket.com/albums/a149/qwiknotch/convert/stang018.jpg)
I just ran pushlock blue hose for the feed and return and cheapo black fuel line for the carb feed, but you can run individual lines to the carb.
I have used this regulator with Weldon f/i pumps as well.
#15
TECH Addict
iTrader: (83)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
On dads Chevelle we have used a Carter mounted just in front of the rear tire. Dead head with a Holley regualtor. When the filter stays clean it is never a issue. Been on 3 power tours and dad drives it every day. We carry a extra pump but have never needed it.
It works and is cheap to do. Recomend adding a oil pressure shut off saved the motor once when the greese zert on the ball joint poked a hole in the remote filter line.
Tim
It works and is cheap to do. Recomend adding a oil pressure shut off saved the motor once when the greese zert on the ball joint poked a hole in the remote filter line.
Tim
#16
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Wow, that was fortunate. I added one for the fire potential in an accident, hadn't thought about it protecting the motor itself.
#17
On The Tree
Thread Starter
iTrader: (9)
Join Date: May 2007
Posts: 101
Likes: 0
Received 0 Likes
on
0 Posts
![](https://ls1tech.com/forums/images/ranks/ls1tech10year.png)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Old thread, but it seems I have made an error here. What I thought was a return line is actually a vent line. So all I have is a feed line and vent line. I have all of it plumbed up in the rear as far as electric fuel pump, filter, tank etc...What I'm wondering is can the vent line be used as the return line?
Nothing is hooked up yet up front but I really kind of feel dumb for not recognizing this earlier, and now might have to go back and redo some of this stuff I thought I had complete. Be easy I'm learning and this is a slow process.
Nothing is hooked up yet up front but I really kind of feel dumb for not recognizing this earlier, and now might have to go back and redo some of this stuff I thought I had complete. Be easy I'm learning and this is a slow process.
#18
Old School Heavy
iTrader: (16)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Old thread, but it seems I have made an error here. What I thought was a return line is actually a vent line. So all I have is a feed line and vent line. I have all of it plumbed up in the rear as far as electric fuel pump, filter, tank etc...What I'm wondering is can the vent line be used as the return line?
Nothing is hooked up yet up front but I really kind of feel dumb for not recognizing this earlier, and now might have to go back and redo some of this stuff I thought I had complete. Be easy I'm learning and this is a slow process.
Nothing is hooked up yet up front but I really kind of feel dumb for not recognizing this earlier, and now might have to go back and redo some of this stuff I thought I had complete. Be easy I'm learning and this is a slow process.