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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 1994 - 1995 Specific Tech

Inline Fuel Pump.

  • Thread starter Thread starter OrangeMustangGt
  • Start date Start date Feb 17, 2006

OrangeMustangGt

Founding Member
Mar 7, 2002
1,976
0
36
Cape Cod, MA
Feb 17, 2006
#1
  • Feb 17, 2006
  • #1
I got ny car dyno'd today, and was told, again that i NEED an additional inline fuel pump before i can turn up my boost past 5lbs. I just did 3 runs today, and found that im running lean at 5psi(due to my new MAF), so i'll have to wait till march when i can get my chip re-burnt, and THEN, i will want to turn up the boost to say 10psi.
 

4Jenna

Founding Member
Sep 12, 2001
4,326
6
69
AZ
Feb 17, 2006
#2
  • Feb 17, 2006
  • #2
What pump do you have now?
 

95cobraguy

Member
Dec 23, 2005
637
11
19
Concord, NC by way of LI, NY
Feb 17, 2006
#3
  • Feb 17, 2006
  • #3
get the walbro gsl 392 inline pump. i just put this one in mine to replace that piece of sh-t t rex. now i gotta get back to the dyno as well.
 

94gts

Member
Jul 4, 2004
873
0
16
Carmel, New York
Feb 17, 2006
#4
  • Feb 17, 2006
  • #4
a single 255 high pressure intank (gss340) should be more than enough. A guy i know made 623 to the tires on pump gas and 18 psi on stock lines and rails in a 90 gt. with that pump of course.
 
M

miran587

Founding Member
Jun 14, 2002
57
0
0
mass
Feb 18, 2006
#5
  • Feb 18, 2006
  • #5
GreenMustangGt said:
I got ny car dyno'd today, and was told, again that i NEED an additional inline fuel pump before i can turn up my boost past 5lbs. I just did 3 runs today, and found that im running lean at 5psi(due to my new MAF), so i'll have to wait till march when i can get my chip re-burnt, and THEN, i will want to turn up the boost to say 10psi.
Click to expand...
i had a regular 255 intank pump couldnt keep up with boost so changed to a 255 high pressure like mentioned above and fixed problem depending on hp but if your making close to 500 rwhp id recommend a inline bbk pump as well good luck
 

94Blue302GT

Member
Oct 20, 2003
704
3
19
Chicago
Feb 18, 2006
#6
  • Feb 18, 2006
  • #6
well, does it have to do with the amount of boost as well as the horse, or is it more just the horsepower? I have a 255, and i plan on running no more than 12 psi, well, until i decide to fry the motor, but if the psi will kill the pump, i'll do other things such as heads and intake etc. first.
 

95cobraguy

Member
Dec 23, 2005
637
11
19
Concord, NC by way of LI, NY
Feb 18, 2006
#7
  • Feb 18, 2006
  • #7
why would you decide to fry your motor? i would think thats the last thing anybody would want to do, unless your in the market for a new one.
 
M

miran587

Founding Member
Jun 14, 2002
57
0
0
mass
Feb 18, 2006
#8
  • Feb 18, 2006
  • #8
94Blue302GT said:
well, does it have to do with the amount of boost as well as the horse, or is it more just the horsepower? I have a 255, and i plan on running no more than 12 psi, well, until i decide to fry the motor, but if the psi will kill the pump, i'll do other things such as heads and intake etc. first.
Click to expand...
change to a high pressure .i needed a high pressure at 10psi making 450rwhp and also added bbk inline for extra insurance
 
M

Monsterbishi

Member
Jan 17, 2006
107
3
18
Christchurch, New Zealand
Feb 18, 2006
#9
  • Feb 18, 2006
  • #9
a Whinebro 255 will be more than enough, generally speaking it's the diameter of the fuel lines used that cause a flow restriction, ideally you want to go up to whatever size matches the internal diameter of your fuel rail, and upsize any filters and fittings on the way.

Personally, on all my previous cars we've run -8AN feeds and a -6AN return, we normally use a Mallory 4305m or similar regulator, feeding both ends of the rail which has -8AN fittings tig welded onto it:



Our 94 GT will be receiving the same treatment when it arrives(19 days!)
 

FlyBy763

Member
Apr 23, 2004
439
0
17
Palm Bay, FL
Feb 18, 2006
#10
  • Feb 18, 2006
  • #10
miran587 said:
i had a regular 255 intank pump couldnt keep up with boost so changed to a 255 high pressure like mentioned above and fixed problem depending on hp but if your making close to 500 rwhp id recommend a inline bbk pump as well good luck
Click to expand...


At what point did your regular 255 go lean? I have a regular 255 and when I got my tune I was going lean at my power levels...
 
M

miran587

Founding Member
Jun 14, 2002
57
0
0
mass
Feb 18, 2006
#11
  • Feb 18, 2006
  • #11
FlyBy763 said:
At what point did your regular 255 go lean? I have a regular 255 and when I got my tune I was going lean at my power levels...
Click to expand...
regular 255 just cant keep up with boost i dont think its so much a hp issue
 

OrangeMustangGt

Founding Member
Mar 7, 2002
1,976
0
36
Cape Cod, MA
Feb 21, 2006
#12
  • Feb 21, 2006
  • #12
thanks guys, i have a walbro 255 High Pressure, and everyone keeps telling me i need an inline pump as whell if i want to turn up boost(although my car has never been out of fuel yet).....So, if i DO need one, what pump complements my intank?...do i want one of equil volume, or greater? thanks
 
M

Monsterbishi

Member
Jan 17, 2006
107
3
18
Christchurch, New Zealand
Feb 21, 2006
#13
  • Feb 21, 2006
  • #13
Running two pumps in series can be a hazardous setup, unless there is a surge tank between them with a return to the tank, otherwise if the second pump is bigger than the first, it will often create so much suction that it will bind up the first pump - this is especially true if they are diaphragm pumps, centrifugal pumps don't usually suffer from this.

Having said that, a 255lph pump should be more than enough fuel, our old car had a 140lph bosch 909 pump and we were turning 300hp at the wheels with no sign of pressure drop in the rail.
 

94gts

Member
Jul 4, 2004
873
0
16
Carmel, New York
Feb 21, 2006
#14
  • Feb 21, 2006
  • #14
94gts said:
a single 255 high pressure intank (gss340) should be more than enough. A guy i know made 623 to the tires on pump gas and 18 psi on stock lines and rails in a 90 gt. with that pump of course. and the fox rails suck compared to ours
Click to expand...

im quoting myself here because i guess no one read it.
 
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