Upgrading Fuel Line

[Zach Gomulka]

The original fuel line in AssHull's pan was shot, so it needs replacing. I'd like to replace it with some stainless steel braided line, but I don't know what size to get, where to get it, what I need to adapt it to the stock tank, AN fittings... Pretty much everything. Motor isn't anything wild, just a 1915, and the plan is to run a CB rotary fuel pump (Carter). We appreiciate your help!

[Jim Ratto]

the size line you use is really dictated by if the line thru the pan will be a "pressure" line or a "suction" line. If you mount the pump up front and send the fuel back to motor, AN-5 or 5/16" is more than large enough.

[louisb]

The original fuel line in AssHull's pan was shot, so it needs replacing. I'd like to replace it with some stainless steel braided line, but I don't know what size to get, where to get it, what I need to adapt it to the stock tank, AN fittings... Pretty much everything. Motor isn't anything wild, just a 1915, and the plan is to run a CB rotary fuel pump (Carter). We appreiciate your help!

Zach,

Get in touch with HotRodVW from this forum or the CLF. (Same name) He does this stuff for a living and can get you good prices as well.

--louis

[Zach Gomulka]

Thanks guys. Pump will be mounted up front. Is AN-5 large enough to allow for future engine upgrades?

[Jim Ratto]

according to AG Bell, 5/16 wil support 300hp naturally aspirated when used as a pressure line. You need to take into consideration what that pump flows too at a pressure suitable to whatever carbs your running. And what his needle valves will flow.

[Zach Gomulka]

According to CB's website:

An internal pressure regulator supplies a constant 3 1/2 lbs. of uninterrupted fuel pressure at up to 30 gallons per hour.

They also advertise a 5 1/2lb version. We haven't bought the pump yet, so it isn't set in stone. I would like to use an electric pump that is quiet, and gets the job done. So if there are any other options out there, I'm all ears.

Carbs for now will be 40IDF's, but an upgrade to IDA's is inevitable

[Jim Ratto]

According to CB's website:

An internal pressure regulator supplies a constant 3 1/2 lbs. of uninterrupted fuel pressure at up to 30 gallons per hour.

They also advertise a 5 1/2lb version. We haven't bought the pump yet, so it isn't set in stone. I would like to use an electric pump that is quiet, and gets the job done. So if there are any other options out there, I'm all ears.

Carbs for now will be 40IDF's, but an upgrade to IDA's is inevitable

Assuming your friend's motor has a VE% of around 75-80% at 6000 rpm, it will ingest about 675lb or air per hour and about 8 gallons of fuel per hour. Even at a VE% of 90%, the motor will use about 9 gallons per hour. Assuming you are running gasoline,

[Diederick/DVK]

so a 3 1/2lbs pump and a stock fuel line will work as well?

[Jim Ratto]

so a 3 1/2lbs pump and a stock fuel line will work as well?

3.5psi is right for Weber needle valves, but I do not know they gph you're needing or what that pump puts out. And, I could not get the stock fuel line to feed my 2054cc IDA motor at high load situations. The motor would run the float bowls dry, even with size 300 needles. Obviously a supply somewhere up stream. I was running Facet pump with 7mm VW hose and stock pipe in pan and stock outlet out of tank. On the freeway, if I ran my foot down hard, I'd get about a mile, and the motor would fall on its face. Kill motor, pull over, look down stacks of carbs and crank linkage.... nothing coming from nozzles.
After a long talk with Jerry and John @ Hoses Unlimited, I went to AN-6 Parker push-lock hose and fittings throughout, along with Holley blue pump and red regulator and Earl's 90-degree AN-6 x 12mm into Webers. I also drilled the inlet passages of carbs (above needle) larger. This finally worked.

Sheep's 1914 IDA motor wouldn't run hard with stock line either. We ran AN-6 thru tunnel and Mallory pump, Holley regulator on his car too.

One thing you might want to think about too: a drag (only) car with a 160hp engine is going to use fuel system differently than a 160hp street car. You might make it thru the quarter mile with what's in the float bowls, but on a long incline, if you put your foot in it, you may not. So think about what you're using the car for. I think a lot of the old drag cars that "made it" on the stock line in the pan worked because they were light for one thing and they were done in 11-12 sec. If they tried climibing the Grapevine here in So Cal with the throttle down, that stock line probably would have starved the bowls. Meltdown.

I think the stock line can supply roughly 150hp. It is only 5mm. All the pressure in the world doesn't create volume. 
More later.

[Diederick/DVK]

alright, i see.

well, i'm gonna have another peek at my steering box and see about that fuel line. will let you know

[Jim Ratto]

alright, i see.

well, i'm gonna have another peek at my steering box and see about that fuel line. will let you know

pay attention to how you FEED the pump... the suction side.

[Diederick/DVK]

is it normal for the fuel line to run like mine? red circle?
what's the "inlet" that i made green for? that looks more logical for the fuel line to run through.

i'm sorry for hijacking the thread but what would be the best way to run an AN-6 line?

p.s. the line exists to the right of my gearbox.

[Zach Gomulka]

I haven't seen that before... You're right, it should go into the frame head where you have the green circle, and exit out it left side frame horn.

I suppose we are going to get some AN-5, and run it the way the factory intended- save for the electric fuel pump and such

[Diederick/DVK]

yup, my car has some messy things of a "restoration" of 15 years ago. the fuel line actually runs underneath the carpeting somewhere. i noticed it when i put that in a few years ago. but i didn't have a clue a fuel line could be that thin.

what i just don't get is how to run it through the tunnel, say i get 10 feet of AN-6 how do i get it to the other end and not get tangled up with the throttle and clutch cable and such... let alone exit it through a tiny peek hole 

[Zach Gomulka]

Access panels in the tunnel will help- if you dont already have them to stiffen up the clutch tube,  I would recommend it. I think I will run the line back to front, until I get to the forward most access panel, then just grab it and stuff it up through the hole in the frame head(?). I made these simple aluminium panels for AssHull's car today...

[Diederick/DVK]

i see what you mean, but mine isn't quite body-off

[Zach Gomulka]

It can still be done

[SlingShot]

Those tie-rods are going to receive a fresh coat, right?

[Jim Ratto]

I haven't seen that before... You're right, it should go into the frame head where you have the green circle, and exit out it left side frame horn.

I suppose we are going to get some AN-5, and run it the way the factory intended- save for the electric fuel pump and such

You might want to consider AN-6 or -8 for feed side of pump

[Zach Gomulka]

I haven't seen that before... You're right, it should go into the frame head where you have the green circle, and exit out it left side frame horn.

I suppose we are going to get some AN-5, and run it the way the factory intended- save for the electric fuel pump and such

You might want to consider AN-6 or -8 for feed side of pump

So why don't I make it all AN-6 then? Or does the feed side have to be larger than the outlet side?

[Zach Gomulka]

Those tie-rods are going to receive a fresh coat, right?

Don't need it. It's pretty warm inside the shop.

[Jim Ratto]

I haven't seen that before... You're right, it should go into the frame head where you have the green circle, and exit out it left side frame horn.

I suppose we are going to get some AN-5, and run it the way the factory intended- save for the electric fuel pump and such

You might want to consider AN-6 or -8 for feed side of pump

So why don't I make it all AN-6 then? Or does the feed side have to be larger than the outlet side?

yes the feed side should be larger.

[Hotrodvw]

I ran all 3/8" line from the pump to tank.  I always do overkill......don't ask me why LOL.  If anything, I make sure the suppyl side of the pump is sufficient. You don't want to starve the pump and burn it up, but I honestly think that matching the supply to your pump inlet is fine. 

This pump uses 1/8" npt ports.  I drilled them out to flow a bit better, since they adapt to #6 male AN. 


I ran 3/8" braided and 3/8" hard line from here to the carbs. 

[Diederick/DVK]

zach, it doesn't look like the CB rotary accepts AN fittings, does it?

[benssp]

they're push fit

[Diederick/DVK]

just got rid of my faulty fuel line. and i found the other one underneath the rubber in the green circle, cut off of course.

zach, you said it should exit in the left side frame horn? i'm trying to locate it. also, should i run a 3/8" hose all the way? isn't that quite thick? i mean i need to run it all the way and don't want it to get stuck somewhere...

cheers!

[Zach Gomulka]

zach, it doesn't look like the CB rotary accepts AN fittings, does it?

It doesn't... I still need to know what I need to mate the two together...

zach, you said it should exit in the left side frame horn? i'm trying to locate it. also, should i run a 3/8" hose all the way? isn't that quite thick? i mean i need to run it all the way and don't want it to get stuck somewhere...

Yep, right out the top of the frame horn. I haven't tried running the hose yet, but it looks like the line should make it all the way through. Just make sure it is clear of the shift rod as that is the only moving part inside the tunnel.

[Hotrodvw]

zach, it doesn't look like the CB rotary accepts AN fittings, does it?

It doesn't... I still need to know what I need to mate the two together...

zach, you said it should exit in the left side frame horn? i'm trying to locate it. also, should i run a 3/8" hose all the way? isn't that quite thick? i mean i need to run it all the way and don't want it to get stuck somewhere...

Yep, right out the top of the frame horn. I haven't tried running the hose yet, but it looks like the line should make it all the way through. Just make sure it is clear of the shift rod as that is the only moving part inside the tunnel.

Zach......post a pic of the pump, I may be able to have a solution for ya.

[Diederick/DVK]

what is it eric? i'd be interested too

[Hotrodvw]

It's not the pump I was thinking of.  I was thinking of an EFI pump.  If you're stuck w/ AN fittings, you an use an AN x barb adapter ad a 2" length of hose.......then run your AN stuff.  I can mock up something here at work, and give you a visual if needed.