Top End Miss
lol im rhick skinned... and as you say it should be sooner on the diag check list...
my only question is with the car stationary vs moving alot of things change, extra force on the fuel in order to get it up the tube... how do you test for that?
That's why volume is important. If you have enough volume at the right pressure, at idle, you'll have enough under acceleration.
I really don't know how to explain this, but I'll try. I'd bet a plumber would know of a good source for theory.
This all presumes no needle, seat, etc. restrictions:
Say you have 3/8 fuel line and 7 psi at idle. Now you change the fuel line to 1/2 and touch nothing else. The fuel pressure would theoretically be lower under load. Now you raise the fuel pressure to 7 psi (under load). More volume as a result. If you just raise the pressure, you'll still have about the same flow. It's restricted by the tubing diameter.
If you have a restriction in your say, 3/8 line, the fuel pressure may still be at 7 psi, but there will be less volume.
If everybody on the street opened their faucets at the same time, but the pipe in the street wasn't large enough in diameter to supply them, all the pressure in the world won't push enough water to the faucets.
I never tried to explain this, it's tough!
If you can put enough gas in the bucket at idle (whatever the amount and time is, I'm not sure), you'll have enough flow under acceleration, and the pressure won't drop off as much because you have plenty of flow.
HELP!