Supercharged Fuel problems - 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 06-20-2006, 12:54 AM
Registered User
 
Join Date: Jun 2006
Location: new york
Posts: 16
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Supercharged Fuel problems

First time posting, I have BDs 1071 blower with dual 1050 holleys. We have a magnafuel 500 pump with a bypass to the tank, we installed a magafuel regulator with the boost reference and the car pops and black smokes at the line, fuel pressure is set at 6.5 and at full throttle we get 13 psi of boost which is 19.5. I disconnect the boost reference, set the pressure to 8.5 and it launches, nothing hard, but then runs out of steam, it is looking for more fuel.

We tried to run a return line regualtor with boost reference and cap off the pump, it takes the regulator pressure (6.5) and makes this the line pressure, so now I am really out of fuel.

I have read some people do not run the boost reference but some do. Can help would be helpful.

thanks

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 06-20-2006, 04:50 AM
poncho62's Avatar
Out of the Loop Moderator
 
Last wiki edit: Streetbeasts links
Last journal entry: at car show
Last photo:
Join Date: Oct 2003
Location: Hanover, Ontario, Canada
Age: 62
Posts: 17,052
Wiki Edits: 5

Thanks: 24
Thanked 344 Times in 266 Posts
moving to engine forum
__________________
Ontario Rodders
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 06-20-2006, 07:54 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
It sounds like you have either some plumbing issues, or carburetion issues. You need to first check with Magnafuel to see how they want you to plumb the system. On a roots style supercharger you would not boost reference the fuel pressure regulator since the carburetors are above the supercharger and only see atmospheric pressure. Boost referencing is normally only done on carbureted applications when you vary the incoming air pressure to the carburetor such as in a turbo or centrifugal supercharged application. On an application like this normally you'd like to maintain between 6.5 and 7.5 psi through your entire run.
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 06-20-2006, 09:18 AM
nitro_baller4692's Avatar
floppers forever
 
Join Date: Jun 2006
Location: illinois
Posts: 791
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
just a thought.if possible in a run look at fuel pressure at wot(wide open throtle).
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 06-20-2006, 11:10 AM
Registered User
 
Join Date: Jun 2006
Location: new york
Posts: 16
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
I will try and run the car with out the Boost Reference to see what happens. The engine builder is telling me to utilize it, but two other of my friend are not running it.
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 06-20-2006, 11:12 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
Who built the engine?
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 06-20-2006, 11:13 AM
Registered User
 
Join Date: Jun 2006
Location: new york
Posts: 16
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
ERD in Canada
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 06-20-2006, 12:18 PM
x007's Avatar
Supercharged T/A
 
Last photo:
Join Date: Sep 2003
Location: Canada
Posts: 277
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
As techBg tell, You dont need boost reference at all !
put your pressure at 6.5 and that's it, problem fixed..

Boost reference is for blownthru or turbo engine! ie: procharger/vortech/paxton etc..
__________________
-= Build for Power =-
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 06-20-2006, 01:06 PM
Registered User
 
Join Date: Jun 2006
Location: new york
Posts: 16
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Thanks for the advice, We will set it and run. I will let you know.

thanks again
Reply With Quote Quick reply to this message
  #10 (permalink)  
Old 06-20-2006, 08:57 PM
camaroman7d's Avatar
Member
 
Last photo:
Join Date: Dec 2003
Location: Vacaville, California
Age: 47
Posts: 2,245
Wiki Edits: 0

Thanks: 3
Thanked 9 Times in 9 Posts
The guys are telling you correctly. Your carbs can't take 19psi of fuel pressure, that's why you were getting the black smoke and poor running engine. You may want to set your fuel pressure a little higher than 6.5 psi, do a little experimenting and see what works best. No boost reference needed.
Reply With Quote Quick reply to this message
  #11 (permalink)  
Old 06-20-2006, 09:02 PM
Registered User
 
Join Date: Jun 2006
Location: new york
Posts: 16
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Thanks, I have a bypass at the pump and a regulator without a return line. I have been told 100 different ways. Any recommendations?

thanks
Reply With Quote Quick reply to this message
  #12 (permalink)  
Old 06-21-2006, 07:24 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
If you're running a Magnafuel system, you should check with them to see how they want it plumbed to work properly in your application.
Reply With Quote Quick reply to this message
  #13 (permalink)  
Old 07-09-2006, 10:27 PM
Registered User
 
Join Date: Jun 2006
Location: new york
Posts: 16
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Okay ran the car with 8 1/2 psi fuel pressue, no boost reference. Off the line the car never hit the wheelie bars, 1000ft mark it broke up. Checked the plugs lean. Added jet, still lean, added more jet, still lean. 92 primary 96 secondarys still lean. Now for the trick question, we have a base timing of 32degrees and have a boost retard for the timing that is set at 1 1/2 Does anyone run a MSD boost retard? Should we just throw it in the garbage and set the timing at 29degrees


thanks
Reply With Quote Quick reply to this message
  #14 (permalink)  
Old 07-09-2006, 11:59 PM
Member
 
Join Date: Dec 2004
Location: Madison, WI
Posts: 1,885
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
Your Dominator can take 10PSI of fuel pressure, that's where we run our big nitrous motors. You have to confirm that fuel pressure is being maintained through the whole pass. Maybe you have but I might have missed it.

A good way to burn up a boosted motor is way too much timing. If your running 13 PSI I'd dial out at least that much timing under boost. 29, no matter what, is way too much in my opinion. Under boost the combustion process will be MUCH faster. 1.5 degress of timing taken out is not a heck of a lot.

I would assume your running decent heads if your base is 32.

Hopefully you plumbed this with -10 hose? We would normally run a bypass back to the cell from the reg versus deadhead the reg on an applicaton like this. But I think you first need to verify fuel pressure all the way down the track.
Reply With Quote Quick reply to this message
  #15 (permalink)  
Old 07-11-2006, 07:13 PM
Registered User
 
Join Date: Jun 2006
Location: new york
Posts: 16
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Thanks for the information. We have dart heads, #10 line throughout. We are going to verify fuel is constant on sunday. Just checked the rest of the plugs and they are all white on top and half way down light yellow.

Sorry for the confusion, we have the dial to take out 1 1/2 degress per pound of boost after 2 pounds. So thats a lot of timing out of the car.

thanks again
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:
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
Fuel/firing Problems with Fuel Injected TPI engine 87 camaro z28 chevcamz28newbie Engine 10 06-13-2009 01:03 PM
anyone have any tricks for vaporising fuel for more mileage? sc2dave Engine 185 11-08-2007 03:07 PM
fuel line problems keys to the classics Engine 2 06-11-2006 05:09 AM
I'm going to make a bonfire out of my car blown69stang Engine 36 08-22-2005 04:36 PM
vapor lock, sbc, hot fuel pump Walker Engine 1 07-19-2004 11:31 PM


All times are GMT -6. The time now is 09:58 PM.


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.