I dont use electric fuel pumps, so need some help.

built a new motor and it was running good, but bogging down on wot from dead stop.

figured timing, then recurved 25 times, idled smooth sounded good, horrible bog, and its a 10:8 compression small block with 2000 stall and 4.10 set up. cant be motor.

anyways, put a new dist in cause i had one, starts up first key, idles for about 20 seconds and dies, just dies.

tuned carb, its almost new. pull throttle back and the pump shot looks weak.

the regulator on the firewall has a guage on it, and it is either broke or accurate, but its showing 2psi. dont even know if a regulator, looks like an old pipe fitting? has to ports for fuel line and top has an allen wrench bolt, then a gauge on it.

if i try to give more gas when dying, it dies, seems like its running out of fuel.

checked vacuum leaks, there are none. The pump whines when key is on, but did that when i got the car. I test drove the new motor about 25-30 times tuning, and nailed it, never a problem. then today it just started.

Spark is fine, carb is 670 avenger, messed with pump cam clearance, idle mix, and springs, thats it.

have other carbs i can use to try, but dont see how the carb would be at fault.


how do i test the fuel components? basically the pump or regulator, so i dont waste money on a part and still have the problem.

its a holley red, motor is a 332, mild cam 270, 670 carb, blueprinted HEI accell, and timing is dead on.

it would explain the stumble alot if the delivery system was going out, it was having enough for mild load, but under heavy load was leaning it.

i dont think the motor needs more carb, i just need to diagose this pump circuit.

thanks in advance.

As long as your pump is at the rear of the car, lower that your tank, it is being gravity fed that should be fine. Since it is a red you could bypass your regulator all together to see if it is the problem. The top of the regulator has an allen head adjustment screw, you can tighten it down for more pressure. My regulator has a guage as well, from the time it was new it never worked right. You could check it with another fuel pressure guage. My red pump if unhooked at the carb will free flow gas in a stream. In fact when I am too lazy to go get gas for the mower, I will unhook the line and shoot it in a 5 gallon can. In no time it is full, like a couple minutes. Hope that helps.

The Red poops out around 7 PSI so it's not really a good pump to use with a regulator anyway. I use them as "helper" pumps for block mounted mechanical pumps (and no regulator).

Regardless, even at only 1-2 PSI it shouldn't cause the kind of idle problems you are describing. On the top end, yes, inadequate fuel pressure can definitely cause problems but at idle the engine is barely consuming much more than a tiny drizzle of fuel.

Did it used to push more than 2 PSI on the gague before the problem started? Maybe that is the right question to start with. What changed when the problem began? Carbs rarely just "go bad" unless you get dirt in them or you mess them up during assembly or tuning. 2 PSI at idle in a weak system could quickly become ZERO when you give it some throttle under load.

well disconnected after regulator it trickles out, no where near a stream.

will disconnect before regulator in the morning.

would be hard to royaly screw up a new avenger by tuning. all i did was idle mix, and pump cam clearance and couple spring changes, its lacking fuel somewhere, 2-3 pis isnt going to feed a high compression motor off any hard start off nailing the gas

was the pump. disconnected right after pump under car, trickled out. Called Holley, said pump inside most likely went out, cheaper to get a new one.

Gauge works, it really was only pushing .5#, no way it could idle period with that, even a mechanical at cranking over is 3-6psi,

No sock on fuel cell or inline filters from the tank to pump, so going to install those, could be a reason why it went out, got bigger wire for ground and a safer hot lead to keep amperage right.

Put a mechanical on as temp fix and runs great, now the timing curves take effect and tuning the carb effects it, just got to get the curve right.