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vw stock tunnel fuel lines... worth upgrading?

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bajachris88 The international telephone dialing code for Antarctica is 6

6,661 posts · joined Apr 2005 ·

#655090
before i run to the plumbers shop, the fuel lines, i have heard that they can be quite restrictive. is this tru?

Is it worth replacing? what guage would u recommend (in mm) and what material?

Copper?

Theres are going into the tunnel, whilst it is stripped, thought of considering as much as a i can, including a return line for any future powerplant/fuel management considerations.

Cheers guys...
(ô_!_/ô) (ô_!_/ô)
69' baja: kombi box, thing spindles, irs, disc front, type 3 rear drums, 2 inch lift kit, 31x10 rears. 👍
New engine in process: 94mm p&bs, 74mm C/w chomol Crank, 35.5x39 SP heads, turbo. Wierd combo, hopeful torque monsta!

555bug WRX Bug Boy

1,123 posts · joined Aug 2002 ·

#655097
i'm no vw expert but I think the standard line is 5mm which is too restrictive for an high hp efi engine, you could use this as a return or breather though. Most brake type shops will sell fuel line, its steal'ish or an alloy as you can bend it by hand if required. I'm running an-6 lines to my engine which is 3/8 or about 8~9mm i believe (not sure if this is ID or OD).
One thing to note it that the standard fuel line is welded in at several locations, you will need to come up with a suitable mounting solution as if its banging aroud it will work harden and become brittle.

bajachris88 The international telephone dialing code for Antarctica is 6

6,661 posts · joined Apr 2005 ·

#655112
with my tunnel currently open for the clutch tube i fitted, was perhaps considering using the stock mounting positions... however enlarged/extended to take the larger fuel line. perhaps a few internal sleeves drilled, fitted with rubber gromments would dampen the vibrations... even if it is siliconed to the metal sleeves, and therefore fastened but in a dampened mannor to soften the bumps.
(ô_!_/ô) (ô_!_/ô)
69' baja: kombi box, thing spindles, irs, disc front, type 3 rear drums, 2 inch lift kit, 31x10 rears. 👍
New engine in process: 94mm p&bs, 74mm C/w chomol Crank, 35.5x39 SP heads, turbo. Wierd combo, hopeful torque monsta!

68AutoBug Beetle Restorer - Experience over 138\% - YIKES --

11,654 posts · joined Aug 2002 ·

#655122
just remember that You don't ever want to open the tunnel again

You could even use copper pipe

and whatever pipe you use, it needs to be permanently
attached to something in the tunnel..
so a pipe with metal clamps would be better than rubber grommets which will eventually crack due to age..

metal hose clamps or pipe clamps etc...
check out a hardware store..

I would leave the original pipe in place as its still useable

and You could clamp another pipe to the original pipe..

cheers

LEE
- Helping keep Air Cooled VWs on the road - location: SCONE in the Upper Hunter Valley - Northern NSW 320 kms NNW of SYDNEY---

Joel Now containing 100\% E-Wang

9,368 posts · joined Feb 2006 ·

#655133
chris i'd highly recomend doing it now while its a nice easy job
id run a 10mm main and a 8mm return
this is the same setup as my black bug has for EFI
even if u dont use 10mm and just use the 8mm for ur main supply for a stock vw engine it allows for easier upgrades down the track

bajachris88 The international telephone dialing code for Antarctica is 6

6,661 posts · joined Apr 2005 ·

#655145
thanks guys, will look into it.

will call to the local plumbers shop for some copper 10mm and 8mm lines. Using copper though, i would have to solder it rather than weld (the shop will be able to tell me anyways).

But ur right, whilst i got it open, i figured it would be worth while.
(ô_!_/ô) (ô_!_/ô)
69' baja: kombi box, thing spindles, irs, disc front, type 3 rear drums, 2 inch lift kit, 31x10 rears. 👍
New engine in process: 94mm p&bs, 74mm C/w chomol Crank, 35.5x39 SP heads, turbo. Wierd combo, hopeful torque monsta!

Camo Custom Title Time!

1,936 posts · joined Oct 2007 ·

#655174
Im in the same position as you with my car body off and a need to replace the fuel line. Someone had run a fuel line inside the car like the brake line (illegal) along the floor.

I have been contemplating using a braided or flexible fuel line down through the tunnel and using cable ties to tie it to the original fuel line. Would also like some feedback re this thought of the flex line.

I to am planning ahead and maybe wishful thinking of efi further down the track, not to mention a little boost. Now I just need to get the car back together and ask the wife for more money 😂
I thought rebuilding a VW would be cheap - Shit I was wrong, just don't let the wife know !!!!

Click here for my (slowy) modded 1961 Beetle build.

Joel Now containing 100\% E-Wang

9,368 posts · joined Feb 2006 ·

#655187
i wouldnt use copper
after working as a fridgy for 4 years i certainly wouldnt use copper
the vibrations and condtions in car copper is too soft for

the stock fuel line is only held into the tunnel by bent over tabs same way as the brake line on the outside
all u would need to do is get some staino hose clamps and clamp it to the original fuel line

welding has to many risks

matberry Moderator Go hard or go home

8,114 posts · joined Mar 2006 ·

#655190
Dont use copper, it will work harden with the vibrations in a car and become brittle and break. Rubber will also degrade over time.
Matt Berry Motorsports...air cooled advice, repairs and mods Ph 0408 704 662
OFF-ROAD,CIRCUIT,DRAG,STREET,ENDURANCE

Adsman Officially Full-On Dubber

393 posts · joined Jan 2007 ·

#655212
If you got contacts and/or cash, instrumentation line used in industry are safe for almost every liquid and they have a range of hold down brackets. If I had a cam handy I'd post some pics. Brackets are made for multiple pipes and sizes with unistrut, bolt, clamp, clip, anti-vibration type of mounts.
What my garage isn't messy........Well chaos is a form of order isn't it?

The Bigfella Officially Full-On Dubber

284 posts · joined Sep 2007 ·

#655221
I did mine with stainless tube - clamped in a couple of spots

bajachris88 The international telephone dialing code for Antarctica is 6

6,661 posts · joined Apr 2005 ·

#655245
Thanks boys,

I have written myself a shopping list for tomorrows runabouts...
Will show some progress shots when the chassis is finished. Depending on how long it takes to source a few iffy bits, i got no idea when it will be rolling out the garage.
(ô_!_/ô) (ô_!_/ô)
69' baja: kombi box, thing spindles, irs, disc front, type 3 rear drums, 2 inch lift kit, 31x10 rears. 👍
New engine in process: 94mm p&bs, 74mm C/w chomol Crank, 35.5x39 SP heads, turbo. Wierd combo, hopeful torque monsta!

BeetleJuice Officially Full-On Dubber

350 posts · joined Sep 2006 ·

#655627
I have a file on Fuel line installation that contains factory instructions.

Send me your email and I can send it to you.

CP
FringeDweller