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right way to set fuel pressure?

  • Thread starter Thread starter 66 Tiger
  • Start date Start date Feb 9, 2004

66 Tiger

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#1
  • Feb 9, 2004
  • #1
My fuel pressure regulator instructions ( BBK ) say to disconnect the vacuum line when setting the pressure.... when I do this & reconnect the line the pressure guage drops? Which pressure setting is the correct one? Also what pres. should I be running? My mods are in my sig. I think I need to update my sig. Thanks.....
 

jrichker

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#2
  • Feb 9, 2004
  • #2
The vacuum line is supposed to be disconnected when setting the base fuel pressure. The pressure is supposed to drop when you reconnect the vacuum line. The lower the vacuum, the more fuel pressure, the more fuel delivered by the injectors.
 
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staticc

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#3
  • Feb 9, 2004
  • #3
did you remember to cap the vacuum hose when you did this?
i just picked up a bbk regulator also.. and remembered reading you must CAP this hose before you set your pressure.

also, you have no engine mods.. only springs, alternator, exhaust etc.

so id run stock pressure which i heard was 39
or go one higher to be on the safe side with 40PSI
 

66 Tiger

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#4
  • Feb 9, 2004
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staticc said:
also, you have no engine mods.. only springs, alternator, exhaust etc.

so id run stock pressure which i heard was 39
or go one higher to be on the safe side with 40PSI
Click to expand...

Thanks for your response but you read the sig for my 86 ( for sale by the way ) I have to update the sig on the 90. I changed out the intake to a gt40 & tmoss ported my lower, also added the BBK 70mm TB & EGR spacer along with shortie headers
 

66 Tiger

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#5
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Anyone else have any advice on the amount of pressure...
 

5.0Droptop

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#6
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around 38-40 psi with out vaccume if heads are stock.
 

BlackFox5.0

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#7
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Im running 42psi, with my mods, I might turn it up a little bit more.... I heard stock is 38psi.
 
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