Cannot lower Fuel Pressure

[6=8]

Some of you may have seen my posts regarding the fun time i'm having getting passed CA Emissions... I have LOW BLMs, and I am attempting to lower my Fuel pressure to get this car lean enough to pass. (Get the BLMs closer to 128 +/-10)

I can only lower the fuel pressure to 37 LBS. While this raised by BLMs from 95 - 109 (25 MPH.. A step in the right direction!), I want to lower the pressure a bit more but this is as low as it goes.

Is this a sign of a kinked or otherwise damaged return line?

This is line off adjustment to 36 lbs, then when I put the Vac line back on, it does not drop.

Let me know if anyone has encountered this situation before. The Adj Regulator is about 1.5 years old... From Kirbans.

How many PSI at idle with the line on is normal?

Thanks! I might be onto something here!

 

[chris2316]

your pump might be flowing more then your regulator can relieve!

 

[XLR8]

It could be a kinked/restricted return line. Those BLMs still seem really low - are you running a Red Armstrong chip? I think my FP is set to 44 line-off and it drops to about 38 with the line on.

 

[6=8]

Replacement Return Line

I now know the pump was overloading the return line! See my post in the emissions area for the results.

I cannot say for sure if the pump is at fault. I may have an internal restruction in the return line that makes this so.

Has anyone run accross this with the Walbro 307? I thought it was good for stock - type applications? I believe there was a pump hotter than this one! (This one sure made quick work of transfering 1/2 tank of gas to another car!)

Also, has anyone replaced the Return line on their GNs? Anyone make a replacement? And 1 more: What is the ID/OD of that little rubber O-Ring that goes on the return line (Under the regulator) mine has deteriourated but still seals.

Thanks!

 

[disco stu]

Lowest I can go is 37# as well. Accufab regulator.

 

[Jerryl]

Lowest I can go is 37# as well. Accufab regulator.

Heard that before. Strange issue as the specs are listed 30 -100 psi.