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

H/C/I fuel system upgrade

  • Thread starter Thread starter DDSTANG94
  • Start date Start date Jan 21, 2007

DDSTANG94

New Member
Dec 9, 2006
465
2
0
FRASER, MICHIGAN
Jan 21, 2007
#1
  • Jan 21, 2007
  • #1
Is anyone running this combo or a similar combo without fuel upgrades.

"AFR 165, performer rpm, and XE270hr cam"

I know I will probably need a lager fuel pump, but what about injectors. Is there any SAFE way to keep the stock fuel components with these upgrades.
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Jan 21, 2007
#2
  • Jan 21, 2007
  • #2
If you run elevated fuel pressure .......
you can make any size inj act a bit bigger

You can fudge with this method ........ just so much.

The talk of this method is always centered around WOT
and
It will work for sure ... again ... by only a certain amount.

however .............

When you up the pressure for Open Loop or WOT

You kinda hose up the Closed Loop side of your tune

Ask yourself this ... What did Ford do about it on the Cobra

Bottom Line on 19's and their abilities ..........

Even mild oem h/c/i combos run risk with stock pump & inj's
unless
You jack up the pressure ... which I like least of all options

Grady
 

mo_dingo

20+ Year Stangneter
Aug 26, 2003
3,031
2
58
Tucson, AZ
Jan 21, 2007
#3
  • Jan 21, 2007
  • #3
The most important thing to do is replace the injectors with at least 24's, 30's would be better. The less the duty cycle of an injector the less likely of injector failure.
 

DDSTANG94

New Member
Dec 9, 2006
465
2
0
FRASER, MICHIGAN
Jan 21, 2007
#4
  • Jan 21, 2007
  • #4
If i ditch the cam do you think ill be alright
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Jan 21, 2007
#5
  • Jan 21, 2007
  • #5
DDSTANG94 said:
If i ditch the cam do you think ill be alright
Click to expand...

NO!

Again ... Just look at the Cobra

Does its heads flow as good as your choice ... NO!

Does its intake flow as good as your choice ... NO!

Does its cam make as much power as your choice ... NO!

See where this is all going!

Plain ole horse sense kinda thing we're talkin about here

Why the fear to upgrade inj's and pump?

Grady
 

DDSTANG94

New Member
Dec 9, 2006
465
2
0
FRASER, MICHIGAN
Jan 21, 2007
#6
  • Jan 21, 2007
  • #6
I fear the injector upgrade because the cost. Its not just the $250 for the fuel injectors that I'm worried about its the mass air meter cost that I'm worried about. With the fuel pump, injectors and mass air calibrated for the injector I'm looking at a $550+ price tag
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Jan 21, 2007
#7
  • Jan 21, 2007
  • #7
DDSTANG94 said:
I fear the injector upgrade because the cost. Its not just the $250 for the fuel injectors that I'm worried about its the mass air meter cost that I'm worried about. With the fuel pump, injectors and mass air calibrated for the injector I'm looking at a $550+ price tag
Click to expand...

I certainly do understand not wanting to spend the money

Aluminum Heads cost over $ 1K
Headers cost $$$ .......
Throttle Body cost $$$ ......
etc etc etc ... $$$



If you wanna make the power
you gotta have that stuff

Just cause you ain't got the funds don't make it not so

If you figure out a way to get the power
without
The large outlay of cash

Be a good guy and let us all know how you did it

Speed cost money! ... How fast do you wanna spend?

Grady
 

DDSTANG94

New Member
Dec 9, 2006
465
2
0
FRASER, MICHIGAN
Jan 21, 2007
#8
  • Jan 21, 2007
  • #8
Point taken.

Fast=cash

no dough=slow
 

m0l0

Member
Nov 20, 2005
178
0
17
Jan 21, 2007
#9
  • Jan 21, 2007
  • #9
DDSTANG94 said:
Point taken.

Fast=cash

no dough=slow
Click to expand...

x1

No cash = Blown HG or worse

I do also understand the "i dont want to spend more" , i my case i used a tweecer with stock maf , of course tweecer runs $500 and a maf $250~, but the tweecer will give you on the first hand a nice stock like idle , the best fan control , and no need for a new maf, but just my 0.02c!
 
M

MustangGT95

New Member
Jul 29, 2003
407
1
0
Jan 21, 2007
#10
  • Jan 21, 2007
  • #10
I just start stockpiling parts. Because it motivates me to get everything else lol. I'll go to get dressed and see a pile of parts in my room and think...damn I need this or that. So I usually scrap money together and buy something.
 

DDSTANG94

New Member
Dec 9, 2006
465
2
0
FRASER, MICHIGAN
Jan 21, 2007
#11
  • Jan 21, 2007
  • #11
MustangGT95 said:
I just start stockpiling parts. Because it motivates me to get everything else lol. I'll go to get dressed and see a pile of parts in my room and think...damn I need this or that. So I usually scrap money together and buy something.
Click to expand...

Ya.. I know what ur sayin thats kinnda what im doin.

Every time I see my AFR...
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Jan 21, 2007
#12
  • Jan 21, 2007
  • #12
m0l0 said:
x1

No cash = Blown HG or worse

I do also understand the "i dont want to spend more" , i my case i used a tweecer with stock maf , of course tweecer runs $500 and a maf $250~, but the tweecer will give you on the first hand a nice stock like idle , the best fan control , and no need for a new maf, but just my 0.02c!
Click to expand...

I was looking closely at your sig

When you dial in your WOT af ratio .........

You may find you peg that oem maf

If not ... I bet you get close to the limit

Grady
 
F

fiveohh94gt

New Member
Dec 26, 2003
277
0
0
Jan 21, 2007
#13
  • Jan 21, 2007
  • #13
final5-0 said:
I was looking closely at your sig

When you dial in your WOT af ratio .........

You may find you peg that oem maf

If not ... I bet you get close to the limit

Grady
Click to expand...

my combo is close to his (except for the cam) and my stock MAF pegged at around 5k on the dyno
 

5ohhh

Member
Mar 31, 2005
88
0
6
Loveville, MD
Feb 17, 2007
#14
  • Feb 17, 2007
  • #14
i just did a combo very close to that and although it is un-finished i was always told that the bigger injectors were always more of a need than the fuel pump. The bigger the injector the less fuel pressure you can run which is easier on the pump. I chose 24's for my combo and that seems to be a very popular choice. 30's are also a good option
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Feb 17, 2007
#15
  • Feb 17, 2007
  • #15
5ohhh said:
i just did a combo very close to that and although it is un-finished i was always told that the bigger injectors were always more of a need than the fuel pump. The bigger the injector the less fuel pressure you can run which is easier on the pump. I chose 24's for my combo and that seems to be a very popular choice. 30's are also a good option
Click to expand...

I just can't buy into that line of thinking

When talking EFI fuel delivery systems ........
You deal with high pressures

Now ... if you up the size of inj ... there is gonna come a point ......
somewhere along the line ... where you won't have the volume
to maintain that needed pressure with the stock pump.

That would be like increasing the size of a garden hose
at the water connection of your house. Sooner or later,
you will find the amount of water is not gonna increase
with a larger size hose because you can't feed more volume
from the water connection.

anyway .......

If you wanna make more power

You gotta pump more air through the motor
Sooooooo
You gotta have the fuel to keep pace with the additional air flow

Yes ... You see it all the time .............

Peeps make a good bit of power with stock inj's and pump
and usually
They get by with elevated pressures

Here is the thing however ..............

If there is ANY amount of inadequacy at ANY point in time
during a WOT condition

You run two risks here

1) Motor Damage is the worst thing that can happen
but still .......
Say you are close to the limit and do no damage

2) You could be leaving power on the table from being too lean

Grady
 

m0l0

Member
Nov 20, 2005
178
0
17
Feb 17, 2007
#16
  • Feb 17, 2007
  • #16
final5-0 said:
I was looking closely at your sig

When you dial in your WOT af ratio .........

You may find you peg that oem maf

If not ... I bet you get close to the limit

Grady
Click to expand...



Yep acording to the tweecer logs I am about 70-100 CFM to peg the maf
 

BlackVert

15 Year Member
Oct 3, 2003
5,589
9
98
Bethesda, MD
Feb 17, 2007
#17
  • Feb 17, 2007
  • #17
that is a great h/c/i combo, but the 19# injectors will not be able to keep up with it. you should have 30#ers. just keep saving and watch the ads over on corral.
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Feb 18, 2007
#18
  • Feb 18, 2007
  • #18
m0l0 said:
Yep acording to the tweecer logs I am about 70-100 CFM to peg the maf
Click to expand...

A thought, tip, or comment ... Or Two

You can find more room by:

1) Raising the scalar ... MAF Voltage Maximum to a value of 4.9999999

2) If using the j4j1 cal file ... Move to the t4m0 maf curve

If you got a WB ...........

When you start to dial in your WOT ratio ..........
You will see the very upper part of the maf curve produces a very fat
mixture. You will see the kg values come down and down as you
lean it out more and more.

Also if you run the j4j1 file ....... You will have the high speed fuel
enrichment come into play as you approach the upper part of
the transfer curve.

Grady
 

m0l0

Member
Nov 20, 2005
178
0
17
Feb 18, 2007
#19
  • Feb 18, 2007
  • #19
final5-0 said:
A thought, tip, or comment ... Or Two

You can find more room by:

1) Raising the scalar ... MAF Voltage Maximum to a value of 4.9999999

2) If using the j4j1 cal file ... Move to the t4m0 maf curve

If you got a WB ...........

When you start to dial in your WOT ratio ..........
You will see the very upper part of the maf curve produces a very fat
mixture. You will see the kg values come down and down as you
lean it out more and more.

Also if you run the j4j1 file ....... You will have the high speed fuel
enrichment come into play as you approach the upper part of
the transfer curve.

Grady
Click to expand...



1.- I havent done that yet but i will give it a shot.
2.-I have already done that since the cobra maf transfer was much more closer to peg the maf volt.

Also the High speed fuel enrichment is disabled but this maf transfer is so extremely fat in the top end that disabling this function didnt show a good leaning , i am having a top end fuel ratio up to 7.2:1 !! this is extremely rich and i will work this as soon as i get back from this travel trip i have right now. also i am having a little trouble handling the spark eec seems to ignore my spark tables and according to the logs i am as high as 47 spark on top end ( i think is more a failure on the payloads not getting right loaded on the tweecer ) but oh well so much work and no time to tune my stang at the moment.
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Feb 18, 2007
#20
  • Feb 18, 2007
  • #20
m0l0 said:
1.- I havent done that yet but i will give it a shot.
2.-I have already done that since the cobra maf transfer was much more closer to peg the maf volt.

Also the High speed fuel enrichment is disabled but this maf transfer is so extremely fat in the top end that disabling this function didnt show a good leaning , i am having a top end fuel ratio up to 7.2:1 !! this is extremely rich and i will work this as soon as i get back from this travel trip i have right now. also i am having a little trouble handling the spark eec seems to ignore my spark tables and according to the logs i am as high as 47 spark on top end ( i think is more a failure on the payloads not getting right loaded on the tweecer ) but oh well so much work and no time to tune my stang at the moment.
Click to expand...

If you'll post up a new thread

I'll talk to you more about this

Lets not continue to hijack the original posters thread

Just paste the above paragraph over to the new thread

Grady
 
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