Before I get send to balalala for this thread, I do know that there is no need for a fuel regulator on an LG-4 engine with stock fuel pump.

I am playing around with my second camaro. I had laying around mallory fuel pressure regulator with guage and decided to put in on the car your because the looks (and is looks great).

Setting the fuel Pressure regulator open (meaning, no pressure restriction) and started the car and saw the pressure (5 psi).... after driving around, I stop on the gas station and decide to check the presurre....to my surprise it was alsmot at zero.. (ENGINE RUNNING with no sign of starvation). NExt day, I did the same thing... started the car, 5 PSI... drove around for a while... 0 PSI.

THis stock pump has a return line. My question is: do this pump some how equalize after a while in the sense of pressure.... What should the pressure be in this type of set up? Is this normal on this stock pump?

 

Gang, any ideas? I have searched with no luck.

 

What kind of regulator is it? What kind of gage is it? Where did you mount the gage?

The pump should put out between 4-6 psi. I'd suspect something with your regulator or gage.

Have you tried adjusting the reg to max pressure and see what happens?

 

Thanks for replying. Is an old mallory 3 way regulator 4309... the return line is plug since the stock mechanical pump has that. The gauge is an oil filled mallory gauge. The gauge connect in the actual regulator.

I wonder if the return line the stock pump has something to do with this drop on pressure....

I will play with the regulator see what happens.

thanks

 

I re-tested my pump by blockin the return line with a clamp. Pressure built up steadily up to 5 psi. I accelerated the engine, and pressure remained (no change for 5 psi)


I played with the regulator and was able to change the pressure. So the pump and the regulator seem to be fine. I guess the return line in the pump equalizes the pressure and prevent built up of it.

My next test will be the volume test.

THX