returnless efi fuel system - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Engine
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 10-27-2005, 05:56 PM
william27103's Avatar
Member
 
Last photo:
Join Date: Jun 2004
Location: North Carolina
Age: 27
Posts: 117
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
returnless efi fuel system

anyone ever seen this before, i saw it in a chevy high performance magazine a couple of monts ago, they built a mpfi system and used a returnless fuel system. can you do that? and how would you do it/how does it work?

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 10-27-2005, 06:39 PM
Siggy_Freud's Avatar
Hotrodders.com Moderator
 
Last photo:
Join Date: Dec 2003
Location: Portland, Oregon
Age: 29
Posts: 2,371
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
I imagine it would be a fairly low pressure system. Or maybe some sort of pressure shutoff switch at the pump? I dont see any logical reason for this and cant imagine any benefits of running this type of system apart from not having to tap the fuel tank.
__________________
Bringing history and technology together.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 10-27-2005, 06:50 PM
1ownerT's Avatar
Home School Valedictorian
 
Last wiki edit: Health and safety in the shop or garage Last photo:
Join Date: Dec 2004
Location: Iowa
Age: 53
Posts: 1,645
Wiki Edits: 4

Thanks: 0
Thanked 3 Times in 3 Posts
Dodge uses a returnless mpfi on the 97-04 Dakotas. I don't know what if any benefits it has, but I have read that people change them to a return type system when making big horsepower changes.
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 10-27-2005, 07:47 PM
william27103's Avatar
Member
 
Last photo:
Join Date: Jun 2004
Location: North Carolina
Age: 27
Posts: 117
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
thanks for info
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 10-27-2005, 10:01 PM
Member
 
Join Date: Dec 2004
Location: Madison, WI
Posts: 1,885
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
The "return" is kept in the tank on a system like this. The benefit is cooler fuel temps as your not "returning" heated fuel back to the tank from the engine compartment/fuel rails. Don't think fuel heats up on a return style system, should have been on Power Tour this year. Lots of tanks TOO HOT TO TOUCH and pumps taken out due to the near 100 degree temps.

A returnless design is a very nice setup, no matter what pressure you want to run. Lots of ways to skin the cat for reliability on high HP EFI applications, this is just one of them, and cheapest.
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 10-27-2005, 10:44 PM
william27103's Avatar
Member
 
Last photo:
Join Date: Jun 2004
Location: North Carolina
Age: 27
Posts: 117
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
how is the return kept in the tank? now i'm confused, and interested, because fuel line and fitting is not cheap
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 10-27-2005, 11:02 PM
william27103's Avatar
Member
 
Last photo:
Join Date: Jun 2004
Location: North Carolina
Age: 27
Posts: 117
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
ok, i looked up some info on returnless systems, and the pressure is controlled by a regulator in the tank, or near the tank that doesn't have a vaccum line attached to it to compensate at acceleration and other engine load levels. the fuel rails then have a constant pressure at all times and it is left up to the ecm to adjust the pulse width of the injectors to supply the engine with enought fuel.

my question is now, can my holley commander 950 ecm do this, or will computers that are designed to work with these systems the only ones that will work. and how would i found out if no one here knows. i guess the best bet with that would be call holley...lol

anyways, if i figure out how to do this, i'll keep everyone up to date, i've got plenty of time for experimenting...

thanks guys
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 10-28-2005, 12:13 AM
aka Duke of URL
 
Last wiki edit: Finding vacuum leaks Last photo:
Join Date: Oct 2001
Location: Rockville, MD
Posts: 4,821
Wiki Edits: 1

Thanks: 0
Thanked 0 Times in 0 Posts
I have a tech article on this somewheres in this mess. The excess fuel is collected in a surge tank instead of being returned to the fuel tank. It is immediately available for hi-pressure/draw need. The drawback is that return fuel is used to cool the main tank pump. This would be for strip/serious street duty only.
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 10-28-2005, 06:52 AM
Technical Support Barry Grant
 
Last photo:
Join Date: Jul 2003
Location: Dahlonega, GA
Posts: 1,503
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Returnless fuel system.

These systems are commonly used on low HP newer street cars. Not something that would normally be used on a race application since compensating for g-force, and response time is going to be much harder in a hi horsepower application.

Yes, a complete return style system will heat up the fuel over time. Generally 1 to 3 degrees for every time it cycles. We've come up with a Heat Sink to help eliminate these problems. When doing duty cycle testing running a pump continuously from a 55 gallon drum we could get the tank too hot to touch in about 7 hours (even with the tank being inside a climate controlled environment. The heat sink would take about 90 degrees of temperature out, and stabilize it. The Power Tour proved lots of problems for guys this year, but non more than for the people who live in places like Arizona. They get days well over 100 degrees, and god only knows what under car temps are with the asphalt, and exhaust.
Reply With Quote Quick reply to this message
  #10 (permalink)  
Old 10-28-2005, 07:13 AM
aka Duke of URL
 
Last wiki edit: Finding vacuum leaks Last photo:
Join Date: Oct 2001
Location: Rockville, MD
Posts: 4,821
Wiki Edits: 1

Thanks: 0
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by Tech @ BG

Yes, a complete return style system will heat up the fuel over time. Generally 1 to 3 degrees for every time it cycles. We've come up with a Heat Sink to help eliminate these problems.
Any chance of posting the description from your catalog or webpage? I would like to see this. Is it anything akin to a fuel cooler?
Reply With Quote Quick reply to this message
  #11 (permalink)  
Old 10-28-2005, 07:21 AM
Technical Support Barry Grant
 
Last photo:
Join Date: Jul 2003
Location: Dahlonega, GA
Posts: 1,503
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by KULTULZ
Any chance of posting the description from your catalog or webpage? I would like to see this. Is it anything akin to a fuel cooler?
Here's a link: http://www.barrygrant.com/news/artic...oduct_005.aspx
Reply With Quote Quick reply to this message
  #12 (permalink)  
Old 10-28-2005, 07:38 AM
aka Duke of URL
 
Last wiki edit: Finding vacuum leaks Last photo:
Join Date: Oct 2001
Location: Rockville, MD
Posts: 4,821
Wiki Edits: 1

Thanks: 0
Thanked 0 Times in 0 Posts
DAMN! Talk about service...
Reply With Quote Quick reply to this message
  #13 (permalink)  
Old 10-28-2005, 07:49 AM
Technical Support Barry Grant
 
Last photo:
Join Date: Jul 2003
Location: Dahlonega, GA
Posts: 1,503
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
We try....
Reply With Quote Quick reply to this message
  #14 (permalink)  
Old 10-28-2005, 07:56 AM
Member
 
Join Date: Dec 2004
Location: Madison, WI
Posts: 1,885
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
Quote:
Originally Posted by william27103
ok, i looked up some info on returnless systems, and the pressure is controlled by a regulator in the tank, or near the tank that doesn't have a vaccum line attached to it to compensate at acceleration and other engine load levels. the fuel rails then have a constant pressure at all times and it is left up to the ecm to adjust the pulse width of the injectors to supply the engine with enought fuel.

my question is now, can my holley commander 950 ecm do this, or will computers that are designed to work with these systems the only ones that will work. and how would i found out if no one here knows. i guess the best bet with that would be call holley...lol

anyways, if i figure out how to do this, i'll keep everyone up to date, i've got plenty of time for experimenting...

thanks guys
Yes the 950 can work fine with a returnless system.

BG, I don't think that heat sink has the btu rejection to have solved the problems we all ran into on PT this year. Many of us literally boiled the fuel in the tank. The solution for some was to coil return fuel line into a cooler prior to returning the gas to the tank.
Reply With Quote Quick reply to this message
  #15 (permalink)  
Old 10-28-2005, 08:05 AM
Technical Support Barry Grant
 
Last photo:
Join Date: Jul 2003
Location: Dahlonega, GA
Posts: 1,503
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by Rick WI
Yes the 950 can work fine with a returnless system.

BG, I don't think that heat sink has the btu rejection to have solved the problems we all ran into on PT this year. Many of us literally boiled the fuel in the tank. The solution for some was to coil return fuel line into a cooler prior to returning the gas to the tank.

Stuck one on a car at the Birmingham stop. He had to stop multiple times, and ice down his tank to make it to AL, but was able to run the rest of the tour, and back home without any problems at all.
Reply With Quote Quick reply to this message

Recent Engine posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Turbo vs Supercharger - Write up!! FastChevyTruck Engine 107 02-16-2011 12:18 PM
Plumbing new fuel system william27103 Engine 13 06-24-2005 01:36 PM
fuel system norm671 Engine 4 01-07-2005 09:38 PM
5.7 vortec fuel system jettman Engine 4 11-26-2003 07:50 AM
Fuel Pressure Variance slomotion Engine 2 04-02-2002 01:25 PM


All times are GMT -6. The time now is 03:46 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.