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Fuel pressure problem??!!

  • Thread starter Thread starter Stang717
  • Start date Start date Sep 23, 2004
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FastDriver

I was uncomfortably high & wearing a helmet
SN Certified Technician
Sep 5, 2001
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Vass, NC
Sep 26, 2004
#21
  • Sep 26, 2004
  • #21
Stang717 said:
Yea, Michael, i tried doin that.. I set it to 40 warm.. and frove for about 30 minutes.. car ran fine at part throttle.. only at WOT was it poppin and choking.. After taking the plugs out, im pretty sure they were the culprit.. i wish i could show them to you, not lookin to good But yea, been drivin for about an hour or so.. driving good as gold.. so, somewhere between the plugs and the cleaning of MAF, something solved it.. Thank god..
anyways, thanks to all..
Mike
Click to expand...

This is exactly what mine used to do. Don't run it at 40 or you'll likely blow a headgasket or worse. Just run it at 55 psi. FWIW, this exactly the same pressure I had to run mine at, and I've seen the same problem on at least 2 other cars. This is what ran the power on the dyno, too.

Chris
 
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Stang717

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Sep 28, 2004
#22
  • Sep 28, 2004
  • #22
Fastdriver, thanks for the info, but just as a recommendation, check your plugs, cap and rotor.. i did this and now i run 42 psi and the car runs beautiful.. 12.8 on the air/fuel ratio..
 
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Stang717

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#23
  • Sep 28, 2004
  • #23
O and, by the way, if you guys were interested.. im not too happy with the results from dyno, but here they are..
262.9 rwhp, and 290.0 trq. time to do a little more wore.. you guys got any suggestions on what other bolt-on i have left, other than charger or NOS??
 

ninety15.0

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#24
  • Sep 28, 2004
  • #24
looks like your tq #'s are real low. Im not too familiar with the gt-40 crate motor, but i have seen dyno #'s from stock 5.0's with minor bolt ons that have similar or higher tq #'s. i think there still may be quite a bit of power in that motor that just needs to be tuned out. good luck man.
 
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Stang717

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#25
  • Sep 28, 2004
  • #25
yeah, gimme some suggestions to bring my torque up.. im still new to the 5.0, so any suggestions would be awesome.... thanks ninety..

I was thinking of doin a chip of some sort..but heard many negatives..

i currently have a NX kit at home, and debating on doin the install or selling it..

I would really love to do a charger, but my wallet thinks otherwise..

thinkin of doin an electric fan swap..
what am i lookin at, 200$ or so?? hard install??

Mike
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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Sep 28, 2004
#26
  • Sep 28, 2004
  • #26
i would not do a fan swap w/o atleast a 3G alternator upgrade. if you already have one, go for it. good luck.
 
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Stang717

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#27
  • Sep 29, 2004
  • #27
3G?? help me out man, im not too good with all the crazy abbreviations.. I know you dont mean a $3000 alternator..

i currently have a motorcraft(or at least shell) 130 amp alternator.. with all my accessories on, fan at high, wipers, lights, radio, it charges at like 12.7 or so..

Is that gonna be pushin it too far??
 

ninety15.0

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#28
  • Sep 29, 2004
  • #28
I would say that if your trying to get your power #'s up, an electric fan isnt gonna get u there. It might be worth about 5 hp. Unless you are having cooling problems or just have a ton of extra cash layin around i wouldnt bother with the fan. Maybe a custom burnt chip thats calibrated to your specific mods might be a better way to get your stang's motor to achieve its full potential. I just dont think those tq numbers you got are as high as they should be for your combo. Seeing as a healthy stock 5.0 puts down around 270 lbs-ft, i think u have some more power in that engine that u need to find. What was your air fuel ratio on the dyno? How did the power curves look? what kind of dyno was it?
 
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Stang717

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#29
  • Sep 29, 2004
  • #29
inertia dyno, air fuel was right at 12.8-13 for each run.. we bumped timing up a bit, and played with the fp. highest torque was at about 4800-5200 rpm..
power curve looked pretty good.. tests were done starting at 2000 rpm in fourth gear..
any suggestions??

Mike
 

FastDriver

I was uncomfortably high & wearing a helmet
SN Certified Technician
Sep 5, 2001
6,065
2,670
224
Vass, NC
Sep 29, 2004
#30
  • Sep 29, 2004
  • #30
Stang717 said:
Fastdriver, thanks for the info, but just as a recommendation, check your plugs, cap and rotor.. i did this and now i run 42 psi and the car runs beautiful.. 12.8 on the air/fuel ratio..
Click to expand...

Thank you for your suggestions bud, but 3 things. Unfortunately, the car was wrecked and hte engine is on a stand, now. 2, the plugs, cap, rotor, and wires were all new and I have played around with them a few times trying different caps and wires. 3, My car put out 320 rwhp and I believe that dispite the information around, 24 lb injectors were just too small at the stock fuel pressure.

edit: BTW, if you want to do an electric fan install without the hassle of the high-output alternator, get a black magic/flex-a-lite electric fan. I've run one for 2 years on a stock-replacement (autozone) alternator without any problems whatsoever.

pps. I notice you've already got a 3G (130 amp) alternator, so you'll be fine with any electric fan. In that case, I reccommend you go the cheaper route and get one off of an SN95 or lincoln or something...

Chris
 
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Stang717

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Sep 29, 2004
#31
  • Sep 29, 2004
  • #31
Nice, good call Chris.. thanks man.. sorry bout the car

Mike

I guess thats what the 3G alternator is
 
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Stang717

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Sep 29, 2004
#32
  • Sep 29, 2004
  • #32
Since this thread kinda went in a different direction already, I figured id throw this out also.. while puttsin around with all fuel issues, i also keep pulling a code 54, (ACT of VAT voltage high)???

Whats up with this, should i get a new sender??

Mike
 
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Stang717

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Sep 22, 2004
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Sep 30, 2004
#33
  • Sep 30, 2004
  • #33
ttt
 
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gt90stang

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#34
  • Oct 1, 2004
  • #34
Check your ACT resistance and if it is out of spec replace it. Sorry can't remember the spec. do a search it should be on here.

Good Luck, Don
 
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Stang717

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Oct 1, 2004
#35
  • Oct 1, 2004
  • #35
Sweet, thanks

Mike
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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Oct 2, 2004
#36
  • Oct 2, 2004
  • #36
gt90stang said:
Check your ACT resistance and if it is out of spec replace it. Sorry can't remember the spec. do a search it should be on here.

Good Luck, Don
Click to expand...
to add to Don's great advice (i could not think off the top of my sorry bean what code 54 was) - Jrichker has posted the values before.

EDIT: here is a link that Joe has posted before with the values:
http://forums.stangnet.com/showpost.php?p=3903611&postcount=6
 
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