74dusterman
74dusterman
Ok, I am sick of the annoying Holley fuelpump on my Duster. Anyone have any suggestions on a good gerotor fuelpump? How many gph freeflow should I have for a 400+hp 340?
electronic fuel pump???
- Thread starter 74dusterman
- Start date
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bad440
everything,all the time..
the mallory comp pump is nice and quiet.about 250.00 from summit or jegs.
stumper
Well-Known Member
With a mild build like that why not go back to a mechanical pump? Rule of thumb ... a motor uses about 1 lb/hour of fuel to make 2 hp at WOT. So for 400 hp about 200 lb/hr.
At a density of around 6.1 lb/gal that comes out to around 33 gph if my calculations are correct .... What you say - only 33 gph??? But why does everyone run these 150 - 250 GPH pumps on street cars ........? Short answer is that most pumps in use are way oversized for their application. Sure you need to factor in for a return line (if you use one), some line losses etc. But even if you sized for a a 50% return rate at WOT that is still only 50 GPH (66 GPH for 100% return - at WOT) that you need. The more the pump is oversized the more heat it generates and more power it uses to run and in general the more noise it is going to make.
At a density of around 6.1 lb/gal that comes out to around 33 gph if my calculations are correct .... What you say - only 33 gph??? But why does everyone run these 150 - 250 GPH pumps on street cars ........? Short answer is that most pumps in use are way oversized for their application. Sure you need to factor in for a return line (if you use one), some line losses etc. But even if you sized for a a 50% return rate at WOT that is still only 50 GPH (66 GPH for 100% return - at WOT) that you need. The more the pump is oversized the more heat it generates and more power it uses to run and in general the more noise it is going to make.
trapster
Well-Known Member
stay away from mr. gasket.
Blue Grey Duster
Well-Known Member
74dusterman That's a good question. I've been looking into the same thing. I don't know much, but from what I've found out, few manufacturers are going to tell you, in their advertisements, what you need to know. Especially if you drag race the car. They mention the free flow and different pressures, but they seldom put it together. Where there is confusion, there is money to be made !
Fortunately edelbrock does tell you a little more in their instructions at Summit Racing website. For $200.00 their 1792 has a free flow rate at 160 GPH. Put some pressure behind it and it falls off to 80 GPH at 6.5 PSI.
Just like putting your finger over the end of a garden hose, pressure goes up and the flow goes down. You have to have flow and pressure, cause you can have empty fuel bowls and 7 PSI at the regulator. I know there are variables, but the flow of 80 GPH is not even close for a 12 second quarter mile car.
It looks like, according to Don at FBO,you would need a minimum of 120 GPH at @ 7 PSI, for a 12 sec. car. Getting into the variables, he suggests 150 GPH. This comes from his Tuning To Win Guide.
Like stumper said, a good mechanical might do.
I agree with trapster, and I don't buy anything from mr gasket. NOTHING.
Which holley fuel pump are you using right now ?
Fortunately edelbrock does tell you a little more in their instructions at Summit Racing website. For $200.00 their 1792 has a free flow rate at 160 GPH. Put some pressure behind it and it falls off to 80 GPH at 6.5 PSI.
Just like putting your finger over the end of a garden hose, pressure goes up and the flow goes down. You have to have flow and pressure, cause you can have empty fuel bowls and 7 PSI at the regulator. I know there are variables, but the flow of 80 GPH is not even close for a 12 second quarter mile car.
It looks like, according to Don at FBO,you would need a minimum of 120 GPH at @ 7 PSI, for a 12 sec. car. Getting into the variables, he suggests 150 GPH. This comes from his Tuning To Win Guide.
Like stumper said, a good mechanical might do.
I agree with trapster, and I don't buy anything from mr gasket. NOTHING.
Which holley fuel pump are you using right now ?
74dusterman
74dusterman
I have the Holley blue pump now. I dont want to go back to the mechanical because I like to turn the key and know the gas is at the carb. My car sits for long periods of time and I have to crank it for a while to get gas back to the carb with a mechanical pump.
mullinax95
Well-Known Member
Mechanical pump or get off the wallet and buy a higher quality pump. Look for a rotary-vane non pulsating pump. They still make some noise. In tank pump will be the quietest.
74dusterman
74dusterman
I am not running a return line right now. Maybe a return line would help because the pump will not be dead heading at the regulator. Can I run a 5/16 return line or will I lose the pressure to the carb.
mullinax95
Well-Known Member
It's been a while since I seen the article but it was in a car craft mag. They had a holley carb with the return line coming off the bowl inlets on the throttle lever side of the carb. Gas coming in the on oneside of the bowls and out the other side (return line). Both front and back bowls was connected. This helped keep the carb cool because gas was constantly running through the carb even while the engine was shut down (switch left on). Good by vapor lock and overload problems. If that worked then I dont see no reason why 5/16s return line would cause line pressure issues.
74dusterman
74dusterman
I ran a 5/16 return line off the regulator and the pressure to the carb dropped to 2psi. The pump was still as noisy as it was before. I am going to buy a gerotor pump and be done with it. :banghead:
cudaspaz
Well-Known Member
My Holley HP 125 gerrotor pump was very quiet but just died on me at a car cruise in last weekend.....pump just got super quiet and quit working altogether.
Luckily I had a back up Jegs vane style pump I bolted on to get me home.
I really liked the HP 125 because it was very quiet and would like to go back with another quiet pump but I am getting tired of electric pumps and the problems associated with them for a street car.
I would love to know if there is an electric pump out there that can be used as a primer for starting purposes and back up for use with a mechanical pump that fuel can flow through while switched off...........I think this will be my best option since I am tired of putting money into electric pumps.
So far I have had a Jegs vane style 90 gph....noisy as hell but works fine.
HP 125 gerotor pump....beautifully quiet but dead after one year.
now running a cheap vane style summit pump 95 gph...loud as hell...drives me crazy.
An in tank pump is too much more trouble than I want to mess with so I think mechanical with a flow through electric back up will be my best bet.
If anyone knows of a good flow through electric that will allow fuel to flow through while not in use, please feel free to chime in.
Luckily I had a back up Jegs vane style pump I bolted on to get me home.
I really liked the HP 125 because it was very quiet and would like to go back with another quiet pump but I am getting tired of electric pumps and the problems associated with them for a street car.
I would love to know if there is an electric pump out there that can be used as a primer for starting purposes and back up for use with a mechanical pump that fuel can flow through while switched off...........I think this will be my best option since I am tired of putting money into electric pumps.
So far I have had a Jegs vane style 90 gph....noisy as hell but works fine.
HP 125 gerotor pump....beautifully quiet but dead after one year.
now running a cheap vane style summit pump 95 gph...loud as hell...drives me crazy.
An in tank pump is too much more trouble than I want to mess with so I think mechanical with a flow through electric back up will be my best bet.
If anyone knows of a good flow through electric that will allow fuel to flow through while not in use, please feel free to chime in.
pettybludart
Well-Known Member
I used a Carter manual pump on a 525hp 410 ci with 5/16 line.I ran a 10.80 @122mph.I,ve since upgraded to a Holley blue pump and 3/8 line.
airwoofer
Drivetrain limit explorer
My 500 HP 416 was using about 40 GPH at full power on the dyno.
Interesting about plumbing a return line at the carb bowls and keeping cool fuel in the carb. May help with a off the line stumble I have been getting when I run with the hood on.
Interesting about plumbing a return line at the carb bowls and keeping cool fuel in the carb. May help with a off the line stumble I have been getting when I run with the hood on.
LXguy
Well-Known Member
Mallory pumps are great. Very quiet and last a long long time.
Either the 4110 4140 or 4150 would work great for you.
http://www.summitracing.com/parts/MAA-4110/
I have a Holley blue on a project car, and as soon as it gets its turn in line that sucker is coming off and a Mallory is going in its place.
Either the 4110 4140 or 4150 would work great for you.
http://www.summitracing.com/parts/MAA-4110/
I have a Holley blue on a project car, and as soon as it gets its turn in line that sucker is coming off and a Mallory is going in its place.
67Dart273
Well-Known Member
I run a lowly Holley red pump and cannot believe how noisy it is. I spent considerable effort building rubber isolators for it -- both between the pump and the clamp, and big rubber isolators between the bolts and the clamp. It has rubber connector hoses to the metal line.
It doesn't really bother me that much, but I REALLY expected it to be quieter
It doesn't really bother me that much, but I REALLY expected it to be quieter
Rubber isolators will stop vibration transfered to the car but do very little for the sound. Cover the pump with something like a plastic container and muffle the noise. An irregular shape like egg cartons will drasticlly reduce sound travel. just remeber when you capture the sound you are also capturing the heat.
Ever see the film Fireball 500 ? The guy muffled a turbine engine with a garbage can. I did the same thing to a small vibra-tumbler at a machine shop where I worked. The garbage can didn't fit its diameter but a igloo type dog house worked well. Coworkers nicknamed my creation Hush Puppy LOL
longarm
Car sold back to original owners
I to am sick of the noise.
Any articles/threads that describe how to install an intank pump,
what was used and how it was plumbed?
There was a thread on here where a member did such an install
with pictures a couple years ago, I've been unable to find it.
Any articles/threads that describe how to install an intank pump,
what was used and how it was plumbed?
There was a thread on here where a member did such an install
with pictures a couple years ago, I've been unable to find it.
66plyValiant
Well-Known Member
a factory intank fuel pump for a daytona or something of that nature will work fine, they run 40 GPH @ 15 PSI, just use it with a regulator. just because you can get $300 fuel pumps don't make them good
you can get the one I'm talking about off of ebay for about $20 shipped to your door
you can get the one I'm talking about off of ebay for about $20 shipped to your door
74dusterman
74dusterman
How much of a pain is it to install the intank pump from a dynasty? I found a Mallory 4070M marine pump for $160 from Summit. It is a gerotor style pump. Have not ordered it yet. Not sure which route I want to go yet.
66plyValiant
Well-Known Member
not bad at all, just take the fuel sock of the bottom of the sending unit and put the pump on, run the pump ground to the sending unit body and power out through and to a relay
cudaspaz
Well-Known Member
That Mallory pump looks very similar to the Holley HP series pumps.
longarm
Car sold back to original owners
gerrys
Well-Known Member
I've run my in-tank pump for a ~2K miles without any issues
(except a cracked float that sank to the bottom of the tank:banghead
It is very quiet - barely audible without the engine running.
My original plan was to run a carb on the 5.7l I was installing
and everything was working fine until I wanted to install the hood
and didn't have enough clearance to close it...
The easiest(?) fix was to install a throttle body (~2" tall) instead
of the carb and use the F.A.S.T. EZ-EFI system. The fuel pressure
was adjusted up to 45psi from 6.5psi by changing to a Mallory 4503
regulator and I haven't had any supply problems (although I really
don't drive it very hard...). There was no noticeable change in sound
from the pump with the pressure change.
(except a cracked float that sank to the bottom of the tank:banghead
It is very quiet - barely audible without the engine running.
My original plan was to run a carb on the 5.7l I was installing
and everything was working fine until I wanted to install the hood
and didn't have enough clearance to close it...
The easiest(?) fix was to install a throttle body (~2" tall) instead
of the carb and use the F.A.S.T. EZ-EFI system. The fuel pressure
was adjusted up to 45psi from 6.5psi by changing to a Mallory 4503
regulator and I haven't had any supply problems (although I really
don't drive it very hard...). There was no noticeable change in sound
from the pump with the pressure change.
66plyValiant
Well-Known Member
I've run my in-tank pump for a ~2K miles without any issues
(except a cracked float that sank to the bottom of the tank:banghead
It is very quiet - barely audible without the engine running.
My original plan was to run a carb on the 5.7l I was installing
and everything was working fine until I wanted to install the hood
and didn't have enough clearance to close it...
The easiest(?) fix was to install a throttle body (~2" tall) instead
of the carb and use the F.A.S.T. EZ-EFI system. The fuel pressure
was adjusted up to 45psi from 6.5psi by changing to a Mallory 4503
regulator and I haven't had any supply problems (although I really
don't drive it very hard...). There was no noticeable change in sound
from the pump with the pressure change.
what I would really like to see is how you got the power out through the factory sending unit, and where did you get the pieces that you used to do so?
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