fuel pressure on 6 pack

[kelly]

I'm running at 8lbs now on my 6 pack 4144-1, 4365-1 carbs. I was told that 5-7lbs are the best range to run.
I have a regulator and going to put it on the get the 5-7lbs. Any thoughts about this from some one that knows the 6 pack pressure range. All help would be nice.
Thanks,

 

[Budnicks]

Depends on what type of Needle & seats your using
But "generally speaking" a Holley Carb like a 2300 2bbl or DBL pumper
either with a normal material stock type "Center Pivot style of Needle & Seat"
controlling your fuel bowls float levels
will handle about 7 psi {+ or - a 1/2 psi} with relatively no issues,
too much more that that you could have issues...

I'd highly suggest buy a book about tuning Holley carbs,
if nothing else good for references...

you could always add a fuel pressure regulator & gauge,
to know exactly what the "flowing PSI actually is",
especially with an electric fuel pump or a high pressure/volume mechanical pump

there's lots of information out there...

good luck & happy Moparing

 

[lewtot184]

some of the smaller/cheaper regulators only have 7/32" that's less than 1/4" for those who may be math challenged) feed orifice. i've done 8lbs but think 6-7lbs is safer.

 

[toolmanmike]

I think 5# is plenty. The volume is more important than the pressure.

 

[68 HEMI GTS]

I think 5# is plenty. The volume is more important than the pressure.

This..

That's all I ever run on both my cars. 5 to 5 1/2. 8# is asking for trouble

 

[kelly]

I put a pressure cage on and it read 8lbs, then I put a pressure reg on and now it read 6lbs.
I'm hoping this will do the trick.
thanks

 

[kelly]

well guess what, The mother ^&%^$&*^ still dies. The fuel pump does not pump gas up to the regulator. I took the fuel line off the pump and put a rag over the filler hole and blew air into the tank., lots of gas. I'm at my wits end with the damn thing. It's put up and not going to be touched for a while.

 

[lewtot184]

what type of pump?

 

[Budnicks]

This..

That's all I ever run on both my cars. 5 to 5 1/2. 8# is asking for trouble

That's why I said "generally speaking", different volumes &
different types/styles of pumps or hose/line sizes, will effect actual "flow rates"

If you have a pump that will flow the same gph rate @ 5 psi
as a pump with more psi to achieve the same rate of flow/volume/gph @ 7 psi

even the style of fittings & sizes of the lines etc., can/will effect actual flow

I personally like using a bypass style regulator too,
with a line back to the tank/fuel cell what ever it may be,
that way it's flowing pressure & not dead headed/not spiked pressure too...

We really need the details of the system, line size, from tank & to the carbs,
the pump size/style & volume gph etc.
electric or mechanical etc.

 

[Seventy]

6#s for mine.. with a carter strip pump...

 

[68 HEMI GTS]

That's why I said "generally speaking", different volumes &
different types/styles of pumps or hose/line sizes, will effect actual "flow rates"

If you have a pump that will flow the same gph rate @ 5 psi
as a pump with more psi to achieve the same rate of flow/volume/gph @ 7 psi

even the style of fittings & sizes of the lines etc., can/will effect actual flow

I personally like using a bypass style regulator too,
with a line back to the tank/fuel cell what ever it may be,
that way it's flowing pressure & not dead headed/not spiked pressure too...

We really need the details of the system, line size, from tank & to the carbs,
the pump size/style & volume gph etc.
electric or mechanical etc.

Nope not disagreeing, gotta have volume. Just stating that if your fuel system is up to snuff there's no reason to run crazy pressure. Sounds like his isn't, or something isn't.

 

[uwss]

I run 7 psi; return style regulator. Pre filter to electric pump and filter prior to carbs. Turn on your pump and see what is coming out of it with the carbs disconnected. Troubleshoot it; keep backing up until you find the issue. Shouldn't take more than 2 hours max by yourself.

 

[kelly]

carter manual.

 

[lewtot184]

if it won't pump gas then there may be a fuel pump push rod problem. on the other hand; if the pump was doing 8lbs and suddenly went to zero thats something else. check everything on the suction side to make sure there aren't any loose connections/cracked or pinched hoses. i have seen the pump arms break. you don't state whether the engine is modified or stock but if your looking for a reliable driver type pump i've found the 6903 carter to work nicely. the high pressure carter can be an issue for driving.

 

[kelly]

Right now I'm running a new cam 400+ lift and all new inter parts for my 440. New 6 pack with holley 4144-14365-1 carbs.
rejetted for cam and lifters. I have stock 5/16 lines to pump and 3/8 line after pump to a holley 12-803 regulator. Then to a pressure gauge. It runs good and at 6lbs till I take it out for a drive, then it want's to die at a stop and then quits and it does not pump any gas out of the fuel pump. I have to prime the carbs to get it started again and it will run for a while the act up again. I have dropped the tank and cleaned it out, blew the lines out from the tank to the pump. New gas filter and hoses. I'm out of stuff to do, but set fire to it, or maybe just shoot it. The pump is a holley HI performance pump. I've changed it twice and it still does the same thing. It all started with it over heating and had a cracked head. I had it all rebuilt with new everything. Now it's this problem.......
I'm thinking my be it's time for a chevy.......
Just kidding, I will find the problem.......

 

[lewtot184]

previous post you stated "carter manual", now you say holley (?). i have had holley mech pumps that wouldn't pump fuel. thats why i don't use them anymore. the fuel pump push rod does need to be checked.

 

[kelly]

OOPS! No it's a carter.

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That's my last thing to do.