fuel pressure question, regulator related

[DSM-Franek]

hellooooo

i have my "base" fuel pressure set at 45psi with the vacuum line off, but when i put the line back on it only drops to about 40-42psi. is this normal?

also, when i try to set my base fuel pressure using my afpr i cant set it lower than about 45psi.. my fuel setup is rewired 255 lph pump, afpr and 660s tuned with a safc 1

thanks in advance!
Frank

 

[DSM-Franek]

i also noticed that ever since i reconnected my fuel pressure solenoid ( i had a vacuum straight off the manifold to the afpr ) and played with the fuel pressure that my throttle position fluctuates between about .2 and 1.5% ???

WTF

 

[95blackGsTurbo]

You should be at 43psi with it off and 37psi with it off. What kinda of AFPR are you using? If you are using a B&M Command Flo FPR because it is cheap, there is a reason, you can't adjust lower than stock fuel pressure. Just above.

 

[DSM-Franek]

like i said im 45 with it off but with it on it only drops about 2 or 3 psi to 42 or 43 psi WTF

 

[95-talontsi]

Well first what kind of fpr are you using? Like previously stated if you have the b&m command flo you cant lower the psi.

 

[DSM-Franek]

im not exactly sure.. it came with the car.. may be a command flow though looks kinda cheap like the ones u "modify" the stock fpr to work with. but like previously stated, with the vacuum off then on i should dro about 10 psi but i only drop 2-3 psi WTF why is this?

 

[95blackGsTurbo]

Because you can't lower the pressure with that style of regulator. Even with the line off.

 

[1stGenRocks]

sounds like a command flo on there. post a picture. whats happening is the 255 is outflowing the regulator causing the pressure to stay higher then normal so even with vacuum connected it cant pull the pressure down like it should

 

[DSM-Franek]

sounds like a command flo on there. post a picture. whats happening is the 255 is outflowing the regulator causing the pressure to stay higher then normal so even with vacuum connected it cant pull the pressure down like it should

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its not a command flo but im not sure what it is ..

 

[GVR4592]

Where is the vacuum line sourced from? That fuel pressure regulator works well, if it's functioning properly, I used the same one for a couple years.

 

[DSM-Franek]

Where is the vacuum line sourced from? That fuel pressure regulator works well, if it's functioning properly, I used the same one for a couple years.

the line is off the manifold now with nothing t'ed into it