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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

Performed the fuel pump wiring upgrade..RESULTS

  • Thread starter Thread starter hotmustang331
  • Start date Start date Dec 1, 2007

hotmustang331

Active Member
Apr 29, 2004
2,967
3
48
Bastrop,TX
Dec 1, 2007
#1
  • Dec 1, 2007
  • #1
Well since I was maxing out the fuel system I decided to do this and it made such a big difference, I wanted to share .

I followed this very detailed writeup CLICKY (99-04 GT guys look at page 10 for the wire colours...ours are pink/grey and pink/black) and bought all the parts. (went to Mothers window tint to find that darn relay! Noone else had it...but you can get them online)

So I did the upgrade and these are the results.

BEFORE @ idle and cruize my duty cycle was 46-48%

NOW @ idle and cruize its around 43-44%

BEFORE @ 10PSI in 3rd gear I was seeing 100% duty cycle @ 5400RPMs

NOW @ 10PSI it hit 89% @ around 5400RPMs and then STAYED right there to 6000RPMs where I let out

BEFORE @ 12PSI in 4th it would go 100% @ around 5400 (maybe/probably sooner) and start leaning out @ around 5700-5800RPMs.

NOW @ 12PSI in 3rd and 4th gear its hits 90% @ 5400 or so and stays right there until I let off

This added ALOT of capability to my fuel system and I HIGHLY HIGHLY recommend this mod to anyone who is near their fuel system limits. This will open up ALOT of room...especially on dual pump apps like mine. I would venture to say it added a good 25% capacity to my fuel system...now its working like its supposed to!

Im running dual Ford GT fuel pumps, 42# injectors, stock lines/rails, 03 cobra tank/basket, and gates hose out of the pumps to the PPRV and then stock hose from the PPRV to the outlet.
I could gain even more by removing the PPRV, but since my fual system will now support more than my shortblock....im not even going to worry about it.
 

speed545

Member
Mar 21, 2003
458
1
18
Montreal, canada
Dec 2, 2007
#2
  • Dec 2, 2007
  • #2
Great,

Should i expect same result on a focus pump set up?

I m maxing out at around 5600 on 3th on a 10 psi set up
 

SaleenGT2001

Well-Known Member
Jul 18, 2005
2,811
4
58
Four Oaks NC
Dec 2, 2007
#3
  • Dec 2, 2007
  • #3
i guess is should go ahead and do the wiring then.

what gauge wire did you run? did you run it from the fpdm to the tank also?
 

BennyBlown2v

New Member
Dec 9, 2004
1,233
1
0
Carmel, INdiana
Dec 2, 2007
#4
  • Dec 2, 2007
  • #4
Awesome! Now I can't decide if I should keep the cobra pumps, do the PPRV delete and wiring mod, then just BAP it later if I need it - or do the wiring mod and throw the focus pumps I have laying around in there haha...

Do you have a Part # on that relay so we can find it online and order it
 

SaleenGT2001

Well-Known Member
Jul 18, 2005
2,811
4
58
Four Oaks NC
Dec 2, 2007
#5
  • Dec 2, 2007
  • #5
is there something special about the relay??
 

hotmustang331

Active Member
Apr 29, 2004
2,967
3
48
Bastrop,TX
Dec 2, 2007
#6
  • Dec 2, 2007
  • #6
BOSCH part # 0-332-209-150 and if you get something else you will need to figure out what pins do what.

Ran 10 gauge wire from battery to FPDM and then piggybacked 10 gauge wire from the FPDM to the tank (outside). Had to lower the tank....basicaly I did the instal just like the writeup says to do it....minus the rediculous part of removing the rear wheel to drop the tank .

Yes speed 545, it will help you out alot. I need to datalog again, but BEFORE this mod, my single GT pump was seeing 8Vs max....never logged with the dual pumps, but it shouldnt change. Basically this wiring mod allows more volts to get to the pump....no matter what type pump you have.
 

SaleenGT2001

Well-Known Member
Jul 18, 2005
2,811
4
58
Four Oaks NC
Dec 2, 2007
#7
  • Dec 2, 2007
  • #7
i have a few relays laying around. i just wanted to make sure there wasnt something special about the one you used. i just washed the car today and put it under the cover for a few more months. i bet i'm the only person who has ever washed a car with no engine in it i'll get around to doing the wiring before the engine goes in
 

hotmustang331

Active Member
Apr 29, 2004
2,967
3
48
Bastrop,TX
Dec 3, 2007
#8
  • Dec 3, 2007
  • #8
^ Nope I watched Andy @ MPH wash Jim Fitz's car last time I was there...it was engine less He was even inside the empty engine bay with a spray bottle of soap/degreaser

Yep if you have a simular relay it should work. I just didnt want to take ANY chances with something as important as my fuel system and go with a specific relay thats proven to work properly.
 

SaleenGT2001

Well-Known Member
Jul 18, 2005
2,811
4
58
Four Oaks NC
Jan 17, 2008
#9
  • Jan 17, 2008
  • #9
i just finished up wiring up my car.


i have to say this was one of the easiest mods i have done so far!!
 
S

SilverBullet00

New Member
Jul 5, 2004
1,150
0
0
Wichita, KS
Jan 18, 2008
#10
  • Jan 18, 2008
  • #10
I did mine last saturday.. I was only able to do it from the battery to the FPDM though... I wasnt thinking and filled my tank full a couple hours prior..

Tomorrow I should get the cobra tank and pumps via fedex and then I will complete the wiring
 
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