• Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

Just so I can say I told you so...

  • Thread starter Thread starter Hoffman
  • Start date Start date Mar 16, 2006
H

Hoffman

New Member
Sep 11, 2004
27
0
0
Mar 16, 2006
#1
  • Mar 16, 2006
  • #1
I've been helping a friend of mine do a 351W swap into his 1989 mustang. We ripped out the old EFI stuff and got everything stuffed in. However this has been the argument.
I personally know that you should not use the factory EFI fuel pump for a carb setup, because of pressure etc. etc. However he tends to think it will work because this person told him so, sort of thing.
So, the setup is as follows, intank EFI pump ran to a Moroso Fuel log with built in regulator (The kind you adjust by putting in the little washers). This has a feed line going to the carb, and another outlet going to the existing fuel return line.
What really gets me fired up, is that the pressure is staying at 7 psi, with the pump running but the engine off. Since we haven't figured out the spark problem yet I couldn't tell you of any issues when running.
I'm a person who gets easily irritated by a person who wants to do a half assed job, especially if they ignore sound advice when I am trying to help them. So is he awaiting an unpleasant suprise, and I get to rub it in his face, or is this cluster*%#& actually going to work?
 
8

86bluecobra

Advanced Member
Dec 20, 2004
4,265
12
69
B.C. Canada
Mar 17, 2006
#2
  • Mar 17, 2006
  • #2
the truth is it can work. I however did not do it that way. i went and got a pick-up for my gas tank ran new 3/8 lines and a new low psi electric pump to a regulator and then to my carb. 7 psi and lots of fuel. much better way to do it i believe.
 

50Dreamer

Founding Member
Nov 14, 2000
688
17
38
CT
Mar 18, 2006
#3
  • Mar 18, 2006
  • #3
I don't have a carb car but correct me if im wrong...Carb cars have larger dia. fuel lines?
 

pb_paulie_b

Founding Member
May 19, 2001
894
0
0
Chaptico, Maryland
Mar 18, 2006
#4
  • Mar 18, 2006
  • #4
That would have to be hard as hell on the pump.
 

69Rcode_Mach1

Active Member
Apr 20, 2004
1,473
1
37
Salt Lake City, Utah
Mar 18, 2006
#5
  • Mar 18, 2006
  • #5
It can be done but it is the wrong way to do it. Atleast he put a regulator on it. Otherwise he would have been scratching his head at why his car runs so rich.
 
H

Hoffman

New Member
Sep 11, 2004
27
0
0
Mar 20, 2006
#6
  • Mar 20, 2006
  • #6
He's using the stock 5.0 fuel pump, and the stock feed and return lines. At first I was shaking my head. However he did get it started, and the fuel pressure at idle was around 7 lbs. Then he tried to drive it, then the fuel pressure spiked to around 14 psi. Heres where im saying I told you so... Then he gets the bright idea to regulate it.... TWICE!!! At this point, I'm done, I don't even want to look at it. I got his used EFI parts and got the hell out.
 
B

blue302stang

New Member
Jan 23, 2006
61
0
0
Mar 20, 2006
#7
  • Mar 20, 2006
  • #7
I am not an expert, but with the carbs you are going to run the lower pressure as stated, but at lower pressure you are getting higher volume, so when using a high pressure pump you will be getting a lower volume which would not be enough to run a carb'd car. Thats why alot of carb'd cars run the big fuel lines, to supply a high volume of fuel.
 

Modular2v

Founding Member
Jun 30, 2002
3,222
23
99
oklahoma
Mar 20, 2006
#8
  • Mar 20, 2006
  • #8
i have two extra holley blues if he wants to do it the right way
 
You must log in or register to reply here.

Similar threads

H
Fuel starvation issues, 91 EFI to carb swap. Car dying after 1-3 gallons used. EFI tank, electric fuel pump, bypass regulator. Dual fed carb
  • hassler
  • Oct 11, 2025
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Replies
8
Views
778
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Oct 12, 2025
nickyb
T
  • Locked
Digital Tuning A9l issue or something else
  • Tufgriz
  • Sep 11, 2025
  • Fox 5.0 Mustang Tech
Replies
2
Views
291
Fox 5.0 Mustang Tech Sep 11, 2025
Noobz347
T
Fuel Looking for a little guidance
  • Tufgriz
  • Sep 11, 2025
  • Fox 5.0 Mustang Tech
Replies
9
Views
365
Fox 5.0 Mustang Tech Sep 12, 2025
Noobz347
S
Fuel ‘88 GT Runs Rich Cold — Fixes Itself When I Unplug Sensors (ECT, MAF, O2, etc.)
  • Sufarry
  • Nov 6, 2025
  • Fox 5.0 Mustang Tech
Replies
12
Views
868
Fox 5.0 Mustang Tech Nov 9, 2025
Mustang5L5
A
need help and advise
  • amps1956
  • Oct 14, 2025
  • Other Auto Tech
Replies
16
Views
677
Other Auto Tech Oct 21, 2025
Mcmahst
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?