Hello, i have a fuel problem with my -84 Camaro its a 350 engine with a Weiand 144 blower and non cc quadrajet.

I use a mechanical fuel pump piston style that is capable to 50 PSI.
but all the time that i go out and drive around, the fuel pressure will drop and the fuel delivery will quit.
It can happen when I'm driving at cruising speed or when i stand still...

And to get the fuel back i have to blow air into the line that goes back to the tank from the coal canister or what its name is

I have one fuel filter in the carb and one filter just before the fuel pump.
When everything is working nice and i open the fuel tank i hear a psyyyy sound.
And when the fuel pressure drops and the fuel delivery will quit and if i open the fuel tank cap i hear no sound.

should there be all the time some kind of a pressure in the fuel tank?

And i got one tip that i should drop the tank and check how bad the sock on the pickup looks and remove the sock totally.....

So before i go and drop the tank does anyone here have any idea what the problem could be??

Please just ask if i forgot to write something.

Thanks