I am running a Carter solenoid electric fuel pump and no mechanical pump. I was having fuel pressure trouble only at high speeds but now I am having trouble at lower speeds too. I am trying to figure out if the line is clogged or if I just don't have enough flow. I did a test and it took 2 minutes for the pump to pump a half gallon of gas. That seems a little slow to me, but I can't find any specs. I had this problem about 8 years ago and it turned out to be junk in the line near the tank. Anyone know how much flow is needed for a mild 455?
A 400 HP 455 takes aproximately 200 lbs/hr of fuel. or aproximately 28 gallons/hour. Add 20% for a safety factor. There is always loss due to line length and bends. Also, keep in mind that most pumps are rated at free flow-- you want the , 4-7 psi pressure flow rating. whatever pressure they rate it at. The last stock 455 STG 1 pump I tested, flowed 26gal/hour, with no suction loss (fed straight from a gas can 2 feet away). JW
So if I am doing my math correctly it would take 4 minutes to pump a gallon which would be 15 gallons per hour. It sounds like no matter what I need to put that mechanical back on there since all the big electrics won't fit in a tidy manner. I'll still drop the tank down, pull the hose off the top and see if there is junk in there. Last time it looked like steel wool was blocking it.
