SBC Fuel Pressure fluctuating

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10-25-2005, 06:24 PM
gherkin350

SBC Fuel Pressure fluctuating

Quick question for those who know.

My mechanical fuel pressue gauge has just gone stupid it fluctuates back and forward so fast I can't read it. My fuel bowls are level and constant. Think it may be a diapraghm issue?? What is good pressure anyway? 7pound???

Standard mechanical fuel pump.
Dual feed holley.
Ventilated gas tank.
Happens at all revs.

WEIRD!

Andy.
10-25-2005, 06:43 PM
NTFDAY

Years ago I had the return spring on the lever break, did about the same thing.
10-25-2005, 07:16 PM
lt1s10

5 to 6 lbs. will work. if it was mine i'd have to check it with another gauge. if you dont have another gauge take the line loose and run some fuel into a bucket and see if the stream of fuel is steady and strong. **)
10-25-2005, 08:28 PM
gherkin350

Thanks I will get on to it.

Andy:D
11-06-2005, 06:31 PM
CamelJoe1985

u may need a higher gallon per hour fuel pump since ur feeding two lines to your carb
11-06-2005, 07:36 PM
Bryan TTM

block it off and go with a Aeromotive pump & reg
11-06-2005, 07:49 PM
erik erikson

Quote:

Originally posted by Bryan TTM
block it off and go with a Aeromotive pump & reg

WHY DON'T WE FIND OUT SOME ENGINE SPECS. BEFORE WE TELL HIM TO GO OUT AND SPEND $ 250 ON AN ELECTRICAL FUEL PUMP.
11-06-2005, 08:05 PM
s10streeter

If a different guage shows the same,make sure you dont have any restrictions in the fuel lines. Old rubber lines tend to colapse, check for crimps in the metal lines. I had a fluctuating fuel pressure guage and turned out that the sock in the tank had become 90% blocked. One it was cleaned out, the fuel pressure went steady. Slim chance that is your problem because you would probably experience starvation with that carb, especially with the secondaries. If it keeps evading you, go ahead and check.:)