Fuel Pump Issue??!!

[Scooterz]

I think I need to buy & new fuel pump. My Holley manual is failing (170GPH) I think & is not enough apparently. I am getting sufficent pressure, but not enough flow at this point?? Here is a brief current setup: Sumped original tank w/ mallory filter @ tank all 10an to pump. Then 8an to reg w/ filter inbetween. from reg 6an to carb which is quickfuel 950hp. Reg is a BP w/ 6 an back to tank. BBC w/ P&P heads, teamG, solid lunatti, about 500Hp. all steel 69 Camaro w/ Th350 & stall.

Symptoms: off idle is fine. mid starts to fail & when secondaries are open for a duration, I get some flat acceleration & poping like it is lean. W/O Acceleration is poor. Carb is new (and larger than last), reg is new, new filters, plugs & wires new. floats set, jets correct, PV (only in primary) checked & is fine. Sound like a pump issue??

I need some electric pump advice. How is Holley blue/black?? I cannot afford the magna flow right now... but I want to get going soon. Have not had to buy a pump in a long time!! Any feed back is appreciated!! Scooter

[twobad1]

ive seen valve spring issues cause similar prob.just a thought

[desoto30]

Yes I would use an on engine valve spring tester & compare your readings against what you set them up at first since this is a very quick check.Then I would do a "fuel can test" to establish what the output of your fuel system actually is before forking any cash on anything,both these tests are free.

[TopspeedLowet]

Yes I would use an on engine valve spring tester & compare your readings against what you set them up at first since this is a very quick check.Then I would do a "fuel can test" to establish what the output of your fuel system actually is before forking any cash on anything,both these tests are free.
How do you do that fuel flow test on a mechanical engine driven pump? Do you use a tee in the line and then start the engine? and at what RPM, FIRE! FIRE!

[desoto30]

how I would go about this would be,hook the carb to an electric pump,with another fuel supply,connect a hose to the output side of the mechanical pump & run the engine @ chosen rpm & then look into the container each time & see how much fuel is there.Yes I totally agree with you to have a fire extinguisher at hand & I would suggest a buddy to assist also

[TopspeedLowet]

how I would go about this would be,hook the carb to an electric pump,with another fuel supply,connect a hose to the output side of the mechanical pump & run the engine @ chosen rpm & then look into the container each time & see how much fuel is there.Yes I totally agree with you to have a fire extinguisher at hand & I would suggest a buddy to assist also
Thank's Desoto30, I was just kidden about the fire, but your method sure is creative. You get an A for that answer by me sir. :) :)

[TheYellaBrick]

Stock or aftermarket fuel tank ? Stock tank will have smaller ID fuel line and a high demand engine will not allow sufficient flow to keep that carb full.

[Scooterz]

Thanks everybody. I want the Holley manual gone no matter what. The motor makes around 500hp, w/ one 4150 950hp flatform. Be it the new carb being starved or the manual pump bad, I just feel an electric is necessary. I have heard of vane style or a g-rotor style.... the g-rotor I am told is better, but requires a BP (which I have). There has to be some folks out there w/ BBC's running Holley blue or Black... on motors like mine... what is your feed back & is it enough? Keep talking to me...


Double -D,

I have a stock 69 Camaro tank that is sumped, w/ 10AN to a Mallory filter, 10AN to current pump. Then 8AN to reg, & 6 AN to carb. 6AN is BP.

[Scooterz]

Desoto-

Ok, I re-read what you are saying & now I understand it. This is mainly a wild street car driven on the street most of the time. I just don't see a pivotal point w/ valve train to cause this. I have done a visual on the heads & confirmed a .26/.26 int/ex valve lash... look good. No visible issues detected in condition of springs & valve train. Off idle is fine... it has symptoms in upper mid to full throttle. I agree with you, as you probaly know more than i anyways. heres my point: I hate mechanicals... this car warrants a electric in my opinion anyways. So no matter what, I am going to pick a pump- what do you think about holley blue/black? Thanks!! Scooter

[TheYellaBrick]

Double -D,

I have a stock 69 Camaro tank that is sumped, w/ 10AN to a Mallory filter, 10AN to current pump. Then 8AN to reg, & 6 AN to carb. 6AN is BP.

Sounds like a tired pump alright. Time for that electric !
Just don't forget that tip over OFF switch !

[cepx111]

Scooter,
I bought one of the Jegs generic brand electric pumps for the boys mustang, works great.
It should work fine for your application as well.
Make sure you mount the pump motor UP and the pump lower than the output of the sump so it can be gravity fed.
I think I paid $69 for the pump and reg. It's just a Holly blue in disguise,
oh and the reg - had a Holley insignia on it.
Goodluck> Cp

[zipper06]

I'm a little confused here, if you are running a regulator, why are you running a return line? I ran a holly black pump, with rear fuel cell and #10 to the reg. set at 8lbs, no return lines with an 850, no issues at all when i was running gas (present car).I still have the setup on the car and can pull the toilet bowl off and put a carb on and switch back from the front mounted tank in less than an hr. I have also ran a manuel Holly with rear fuel cell and 1/2 Alum. (on another car) line to the pump and #8 to a fuel log/splitter to 2 660 center squirters mounted side ways with large bowls. i'm not saying that the pump isn't bad i'm just thinking that you could be draining off the volume with the BP. I wouldn't run a BP on anything except a manuel front mounted injection pump unless it was after the carbs. The tunnel ram with 660's was an 8,000rpm motor ever pass. At one time i had a 5.83 gear with10.5X28.5 Micky's and it ran 127, i had a 9200 chip in it, and it never ran out of gas. You may also have a filter restriction on the flow from the tank to the pump. If i were plumbing it i would have no filter going to the pump, and 1 inline filter #8 to the fuel log after the pump and no return line.

Has worked for me in the past.

JMO

Zip.

[desoto30]

I think that you should also look at Holley's HP series of pumps(HP 125 & NP 250) they are a gerotor style,& very quiet(compared to Holley blue/red,or BG)We have used them now for a few years in fact when I spoke to Holley Aust,he said that we were the first to use one here that he knew of.I like them even though we consider their HP rating optomistic. They are reliable,although we only have used them in limited use applications.They're not expensive either!

[dparker]

I'm a little confused here, if you are running a regulator, why are you running a return line? I ran a holly black pump, with rear fuel cell and #10 to the reg. set at 8lbs, no return lines with an 850, no issues at all when i was running gas (present car).I still have the setup on the car and can pull the toilet bowl off and put a carb on and switch back from the front mounted tank in less than an hr. I have also ran a manuel Holly with rear fuel cell and 1/2 Alum. (on another car) line to the pump and #8 to a fuel log/splitter to 2 660 center squirters mounted side ways with large bowls. i'm not saying that the pump isn't bad i'm just thinking that you could be draining off the volume with the BP. I wouldn't run a BP on anything except a manuel front mounted injection pump unless it was after the carbs. The tunnel ram with 660's was an 8,000rpm motor ever pass. At one time i had a 5.83 gear with10.5X28.5 Micky's and it ran 127, i had a 9200 chip in it, and it never ran out of gas. You may also have a filter restriction on the flow from the tank to the pump. If i were plumbing it i would have no filter going to the pump, and 1 inline filter #8 to the fuel log after the pump and no return line.

Has worked for me in the past.

JMO

Zip.

Rigsby I agree with zipper. You don't need a bypass with a Holley blue/black. Maybe if you had a BG 400 or Magna Fuel 500. Change out your regulator first and see what happens. Might save a little monies.

[Scooterz]

Double/Cp/Zip:

This is my first race car... never had anything this wild... so my knowledge is based on more street friendly applications w/ alot more OEM parts. This is why I have struggled w/ this fuel system so much. the car was set up for drag only when I got it.. it had no BP, 10psi, no regulator, different carb, with the Holley manual pump. Hell, it loaded up too much & got some ring wash... so I installed a BP & a regulator along with a new carb too... it was made to stage & go set up the way it was.

FF to now... I have no fuel log for starters. Just the Mallory FF after sump tank, then a small inline #8AN filter before BP Reg. I am running a return line because I thought it would be better for street driving. To me, it makes sence to install a electric pump as you guys say w/ some gravity just past the tank, & wire it to the battery in trunk w/ about a 40 relay in between, install a block plate for the manual, & be done. I do have the on/off switch on back. Keep talking to me.... help me...

[bjuice]

X2 with ZIP..I also am not a Big fan of Double filtering fuel lines...just not ideal for optimal fuel flow.

Also a Big mistake most people over look is the Rated fual flow of filters Vs the flow rate of the pump...Many people all too often do not have enough flow on the filter side to keep up with the pump..the double filtering just ads to it..

Just my take on it Scoot

[TheYellaBrick]

Ideally you want to PUSH through a filter. A fine meshed, heavily restricted or plugged filter BEFORE the pump can burn a pump up as they use the fuel as a form lubricant. Also why you want to mount an electric pump BELOW tank outlet so you have gravity helping to prime said pump.

[Scooterz]

Gentlemen, thank you. I have newer decent "dead head" style (reg non-bp) that I can use w/ the new pump too. I figured with the flow & fuel system I have now, a BP would be good for street... I was worried I was getting over flow & needed some escape for street use. If this is not an issue, I have no problem deleting the BP & reg. Tell me this.... what is the appliaction/purpose of BP system??

Desoto- I have heard the gerotor style pumps are a little more stronger in the flow department w/ less fluctuation... seems like the better of the sytles (vein -VS- gerotor).

Juice, I understand the 2 filters prior to the carb therory... that makes good sense.

This car must have had wild motor in it at one time, as it has 2 10AN's off of the tank sump indicating to me that it may have 2 pumps at one time. I just want it to have flow for street & occasional strip runs... thanks everyone & God Bless, Scooter

[chevyfireball]

You have bypasses because the pump is flowing a lot of fuel and the regulators are restricting fuel flow down to about 6 lbs so you want excess fuel going back to the tank so the pump isn't straining itself to death. Whether you're idling or going 200mph, the electric pump is pumping the same rate.

I had a mallory 140 and it was useless on my 572ci Camaro. I switched it for a BG250 and that was fine. Originally it was mounted in the trunk with a BG400 I used for the nitrous but after a burnout the car cut out because of lack of fuel and gravity etc. I dropped both pumps under the car and it was all good. Spend the money now on a decent pump. Save you in the long run. You don't want an engine leaning out.