What size fuel line is absolutely required?

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JeffisOld

JeffisOld

Old, Ugly and generally Disagreeable!
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Folks, I am installing a 512 stroker in a 69 Dart abd I am tired of doing things twice.

I will eventually have either a Sniper or FAST system on and the goal is 600-700 HP. I would not think that's at all unreasonable for a mostly street car.

The question is will -8 line be required, or will -6 be adequate to not create lean cycles?

Also, will I be able to run a carb off an efi pump with a good regulator and the return line plugged?

Too many mistakes have cost me money so I may have to run my 950HP for a while.
 
go with #8 line so you aint gonna need to do later

you should also make a decision on brand and wich fuel pump you're gonna use
diferent fuel pump need diferent line so...
 
-8 if you don't want to do it twice. -6 will probably work, but why take chances?
 
72Dart6pack said:
I'd go with a #12 You can never have too much Fuel.
:thumbsup:
Click to expand...

Are you serious 72dart6pack?

I DO NOT plan to run in Alcohol Funny Car!

I'm an older man that has had cataracts removed from both eyes and 2 detached retinas. NHRA would never license me!
 
Everyone run E85 now a days. Thought you needed the volume for that 950HP motor
 
Trust me. I know about fuel flow issues. Yes this is mine.

IMG_25071.jpg
 
72Dart6pack said:
Trust me. I know about fuel flow issues. Yes this is mine.

View attachment 1715238362
Click to expand...

The 950HP to which I referred was a Holley double pumper 950 high performance series carb I bought for my last race car.

Maybe I am showing my age but it was a state of the art carb when I bought it.

I'm getting the feeling maybe I should sell it and look for a Quick Fuel or something.
 
to big of a line and the pump have a harder job for pushing the gaz
under hard acceleration , like I said you should decide on what ever
pump you wanna run with the built your making there and run the line
the pump builder he is sugesting you

I ran the same pump for the last 12 years ( holley black pump )
for a 410 cu.in. with nitrous with a #10 line and 2 regulator
one for the carbs and the other for the nitrous setup
did great but NOW IM GETTING OLD

and i wanna change the pump for one that make lest noise
and the way I see it I will need to change everything as gaz line
because about every company will suggest diferent size of line
even for the return line so ... contact the manufacturer of the pump
your choosing or you have and ask them advice

they built there pump so they should give you the correct size of line you need
 
JeffisOld said:
Folks, I am installing a 512 stroker in a 69 Dart abd I am tired of doing things twice.

I will eventually have either a Sniper or FAST system on and the goal is 600-700 HP. I would not think that's at all unreasonable for a mostly street car.

The question is will -8 line be required, or will -6 be adequate to not create lean cycles?

Also, will I be able to run a carb off an efi pump with a good regulator and the return line plugged?

Too many mistakes have cost me money so I may have to run my 950HP for a while.
Click to expand...
I have a 512 in my A body and use -8 supply line and -8 return. No issues here.
 
crazy 340 said:
to big of a line and the pump have a harder job for pushing the gaz
under hard acceleration , like I said you should decide on what ever
pump you wanna run with the built your making there and run the line
the pump builder he is sugesting you

I ran the same pump for the last 12 years ( holley black pump )
for a 410 cu.in. with nitrous with a #10 line and 2 regulator
one for the carbs and the other for the nitrous setup
did great but NOW IM GETTING OLD

and i wanna change the pump for one that make lest noise
and the way I see it I will need to change everything as gaz line
because about every company will suggest diferent size of line
even for the return line so ... contact the manufacturer of the pump
your choosing or you have and ask them advice

they built there pump so they should give you the correct size of line you need
Click to expand...

Crazy, Thank you!

You bring up a related question I had not even considered - NOISE!

Just for a street car I cannot afford a grand for an Aeromotive set up like i saw yesterday on-line. Who makes a an pump of adequate quality that is not sounding like a leaf blower?

I too am old, this is a toy!

Too may years of turbine engines has made that noise intolerable!
 
Depends on the pressure. If you are eventually going to go with EFI then plumb it now for EFI and be done with it. Put a high pressure pump inside the fuel tank and then use #6 lines for both feed and return. You could probably use a #4 line for return but dual #6 lines will work.

Dual #6 lines will work just fine with EFI since you are operating at higher pressure. (If you don't believe then go to your local Dodge dealer and look at the fuel lines on a Hellcat. Yep, #6)

The trick will be if you stick with the carb. In that case you'll need a regulator which can handle the high pressure from the EFI pump and regulate it down to carb pressure. You'll end up not needing that regulator anymore once you switch to EFI. The Sniper wants 58 psi so you should put a pump in the tank that can handle 60 gallons or 300 lbs per hour at 60 psi. That should be big enough for 600 hp on EFI.
 
AndyF said:
Depends on the pressure. If you are eventually going to go with EFI then plumb it now for EFI and be done with it. Put a high pressure pump inside the fuel tank and then use #6 lines for both feed and return. You could probably use a #4 line for return but dual #6 lines will work.

Dual #6 lines will work just fine with EFI since you are operating at higher pressure. (If you don't believe then go to your local Dodge dealer and look at the fuel lines on a Hellcat. Yep, #6)

The trick will be if you stick with the carb. In that case you'll need a regulator which can handle the high pressure from the EFI pump and regulate it down to carb pressure. You'll end up not needing that regulator anymore once you switch to EFI. The Sniper wants 58 psi so you should put a pump in the tank that can handle 60 gallons or 300 lbs per hour at 60 psi. That should be big enough for 600 hp on EFI.
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^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
FAST 2.0 / 1200 cfm throttle body / 505" wedge . Not dyno`d, but 3 engine programs say 755ish
horsepower. Running a -06 feed line, "it came w/ the fast 2.0 kit." Already had a braided steel -08 feed line hooked to the new 3/8 fuel pick up . Cut the sock off, leaving the pick up as long as possible to avoid airation on the return, which is NOW the ORIGINAL -08. sounds backwards but
Like Andy said -06 is big enough ! The 2.0 runs at only 43 pounds pressure too..
 
Yes, a 3/8 line (#6) is plenty big for EFI. If someone wants to do the math it isn't too hard. 700 hp needs 350 lbs/hour of fuel which is basically 60 gallons per hour. Look up a flow rate calculator on line for 60 gph in a 3/8 tube and you'll see that it is well below the critical velocity. There are flow rate charts on the web that show you what line size you need for how many GPH. The tough math has all been figured out for you so you just have to look up the number on a chart.
 
QFT are making great pump but ounce again the price is there !

HOLLEY are making the gerator pump but as I know they dont last for long !!!Holley HP Series Fuel Pumps 12-125

there is one a little bigger but it have the same problem of longetivity so...

magna fuel , QFT , WELDON are the way to go but money arent falling from
the three where I live so ...

for me waiting a little and gonna do it with the QFT 230 with #8 line
http://documents.holley.com/99-30-230rev3.pdf

my 2 cents
 
crazy 340 said:
QFT are making great pump but ounce again the price is there !

HOLLEY are making the gerator pump but as I know they dont last for long !!!Holley HP Series Fuel Pumps 12-125

there is one a little bigger but it have the same problem of longetivity so...

magna fuel , QFT , WELDON are the way to go but money arent falling from
the three where I live so ...

for me waiting a little and gonna do it with the QFT 230 with #8 line
http://documents.holley.com/99-30-230rev3.pdf

my 2 cents
Click to expand...
Been using the edelbrock 160 for 10yrs+ now. 0 issues.
 
AndyF said:
Yes, a 3/8 line (#6) is plenty big for EFI. If someone wants to do the math it isn't too hard. 700 hp needs 350 lbs/hour of fuel which is basically 60 gallons per hour. Look up a flow rate calculator on line for 60 gph in a 3/8 tube and you'll see that it is well below the critical velocity. There are flow rate charts on the web that show you what line size you need for how many GPH. The tough math has all been figured out for you so you just have to look up the number on a chart.
Click to expand...
Agree, now all I had was a 383 but 3/8 line fed that engine fine (Carter electric pump)
 
Well, this may be blasphemy to some but I am going to put a cell in the car I believe. That way seems to be the least cost prohibitive way to get an in-tank pump (looking for quietest possible) set up. The original tank is not trustworthy and I am not trying to maintain originality anyway.

Any advice from the more experienced than I!
 
-8 line [1/2"] would work just fine. I run my 67 Barracuda with 440" and 4.10 gears. [1/2" fuel line; then -6 split at the regulator to feed each fuel bowl]-[Note this is a 1050 CFM carb.] This car runs 10.70's @ 124 most all the time. [Through the mufflers on Radials]

IMG_0240.jpg


IMG_0234.jpg
 
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