[stevehemi]

My fuel pressure is set at 7lbs at my gauge on the cowl. It was set at 1500 rpms as per Magnafuel. While running, whether it's racing, street driving or just idling the pressure will drop below 4lbs.
Description of the system:
Aluminum fuel cell
#12 line from cell to pump
Magnafuel 500 filter and pump unit
#10 line to Magnafuel log and regulators
#6 line going to the carb and plate.
Power comes from twin relays mounted near the battery next to the pump
so there's no volt or amp loss.
Autometer Procomp liquid filled gauge.
I've double/triplle checked everything I can think of.
Any ideas would be appreciated.

Thank you - Steve

 

[stevehemi]

#8 vent, Filter looks clean, not a spec, Race fuel with foam in the cell, I was thinking may gauge but the car feels flat as the pressure drops.

 

[stevehemi]

i had the teflon plungers swell in the reg...
do you know how to purge a liquid gauge?

I"ll Check the plungers and no I don't.

 

[stevehemi]

-8 vent is to small for -12 supply

Does it idling. Should enough vent.

 

[stevehemi]

theres usually a rubber plug on the back...drain a little glycol or air out...needle should move...
They can move from heat.. it may have been wrong when you set it...
This goes for any liquid filled gauge that sees heat...

I'll try that too. Thanks

 

[stevehemi]

Liquid filled gauge is my bet. Change that and I bet you'll find your problem.

Gonna order one right now without liquid.