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Fuel Pressure Rec's???

  • Thread starter Thread starter cjhenry01
  • Start date Start date Mar 26, 2004
C

cjhenry01

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Mar 21, 2004
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Mar 26, 2004
#1
  • Mar 26, 2004
  • #1
Where should I set my Fuel Pressure? Please see my mod's.
Currently with the car running at idle & with the vaccum connected mine is reading 35-36.
Also, How exactly do I set it? I know I should disconnect the vaccum, but do I disconnect it with the car running or not running?
 

BlackFox5.0

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Aug 7, 2000
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Mar 26, 2004
#2
  • Mar 26, 2004
  • #2
Disconnect the vacuum with the engine running, and read your gauge and set the pressure.

If you have read other similar posts like this one then you will know that asking where to set the pressure is like asking what you should set your timing at.

I'd start with 38-40psi with the vacuum off and go from there and see what makes the most power.
 
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cjhenry01

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Mar 21, 2004
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Mar 26, 2004
#3
  • Mar 26, 2004
  • #3
Thanks, I will give it a try.
 

5.0Droptop

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Mar 26, 2004
#4
  • Mar 26, 2004
  • #4
Id say your at about 40 right now since with vac on it drops 4-6 #
 

jrichker

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Mar 27, 2004
#5
  • Mar 27, 2004
  • #5
Get one of your buddies to ride along with you. Find a level stretch of road where you can do some testing. Don't choose a speed range that will make you shift gears, the shift quality & speed will affect your results. Use 2nd or 3rd gear and do a run from 2000 RPM to 5800 RPM. Call out the RPM as it increases and have you buddy record it and the elapsed time. If you have one of those cheap digital watches like I do, a stop watch is built in. Start the fuel pressure at 36 PSI, vacuum off and make a run. Turn it up to 37 and make another. Be sure to reconnect the vacuum every time you set the pressure. Keep turning up the pressure and making runs until you notice a drop off in time. If your bud was careful to record the results, you'll have a nice chart to use to find the optimum pressure.
 
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Horsepower67

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Feb 1, 2004
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Mar 28, 2004
#6
  • Mar 28, 2004
  • #6
What "vacuum" are you guys referring to? Where is it, and how do you disconnect it?
Thanks,
 

siege

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Feb 23, 2003
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Mar 28, 2004
#7
  • Mar 28, 2004
  • #7
the vacuum line that connects to the fuel pressure regulator. just pull it off.
 
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sublime29

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Mar 18, 2004
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#8
  • Mar 28, 2004
  • #8
Pull the vacuum line off the regulator and plug it.Its right behind the throttle body on the fuel rail.If you have the stock regulator there is no way to adjust it.You need a adjustable one.
 
T

TheUser

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Jul 25, 2003
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Mar 28, 2004
#9
  • Mar 28, 2004
  • #9
uhh...plug it why? You put it back on after you adjust the fuel pressure...
 
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sublime29

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#10
  • Mar 28, 2004
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When you unplug it you will create a huge vacuum leak!!
 

jrichker

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#11
  • Mar 29, 2004
  • #11
sublime29 said:
When you unplug it you will create a huge vacuum leak!!
Click to expand...

Not a huge leak since the line is so small, but it may upset the idle a little. I don't worry about it, since the power brakes and PVC pull more vacuum than the loose vacuum line for the fuel pressure regulator.
 
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