What size fuel lines - Metro Turbo
Turbo Mini Forums

Hi,

I have a metro turbo Mini and have fuel in and return pipes. At present these are flexible hoses that run underneath the car.

I am looking to replace with Copper pipe under the car and flexi hoses from copper pipe to tank and to Carb etc.

I have seen several topics about what size pipes to use. I recnelty purchased some 10mm OD (about 8mm ID) copper pipes from a plumb center but im wondering if these will be too large. And perhaps I should buy the 8mm OD (about 6.5mm ID).

What are the issues with too much fuel being allowed through and too lesss fuel ?

What size is best ?

I bought the car as a project and have neve had the thing running so the old pipes may not be goo enough for the job, which is why im trying to work out the sizes needs to a turbo install.

I have a bosh electric fuel pump installed in the tank


Thanks

for what it is worth, I'm running 8mm OD copper for the supply and 10mm OD for the return on mine

.

Edited by wng691s clubby on 20th Dec, 2013.

Done now needs redoing lol

Thats for the reply Rob, why is the return larger than the supply ?.

Do you have any issues with running the 8mm OD ?

Cheers

doesnt really matter about the OD its the ID that does!
8mm ID is working for me

Reading up on RTS Clutches

The idea is you want next to no restriction in the return line otherwise you can get unstable fuel pressure
And for what its worth im running 10mm for both on the mini
Major over kill but i got 25m micro bore copper pipe for next to nothing

Yes i moved to the darkside

Instagram @jdm_brett

could have done with this post about 9 months ago

Reading up on RTS Clutches

why? i thought it was a 9month old thread for a minute then but now im just confused

On 20th Dec, 2013 WRLondon said:

could have done with this post about 9 months ago

Yes i moved to the darkside

Instagram @jdm_brett

I think I will stick with my 10mm (OD) - 8mm (ID) copper pipe and give it a blast. It will certainly be a tighter fit sticking flxible pipe over the top, since most sizes are 8mm or 9 mm ID.

i had a restrictive return line causing fluctuating fuel pressure and took me about a month to figure out

those sizes should be perfect bamptini, whats the engine spec and boost & fuel pump pressure?

Reading up on RTS Clutches

I have used 8mm microbore copper for both feed and return on both cars and had no problem, with close to 140 bananas.

Does any one know if my soldered joints are going to be at risk from E5 (or E10 in future) ??

couldn't see how the alcohol would affect your silver solder joints id be more worried about the material of your flex lines...

im planing on using 85% my self ive chosen the taipan brand

Nitrile rubber with stainless overbraid OK ?

from my brief Google search Nitrile rubber should be a good choice and the ss braid is a good thing to just a pain to handle!

this chart may be of some use?
http://www.hoseandfittings.com.au/Chemical...nce%20Chart.pdf

Hi WRLondon, sorry for the late reply, ive been busy over Xmas getting a new bathroom fitted, so not had any time to work on the min and read the replies. Thanks for the input, my spec is as follows..... BTW, Ive not mansagfed to have this running yet, Had all new wiring loom fitted a few weeks back, so next job is to connect fuel lines and see what happens

New metro turbo block, re bored to 1293 painted red
Forged Omega pistons 18cc for high boost, new rings
Balanced turbo con rods
Turbo balanced crank
Phase 2 Avon bar cam
All new bearings
Metro turbo head. New exhaust and inlet valve’s, stem seals, custom double valve springs, MED yellow 1:5 rocker set and push rods, polished, ported and gas flowed head, massive chambers for high boost
Alloy finned rocker cover
Drilled 11 stud
ARP studs and nuts
New exhaust studs and copper nuts
Custom laser cut one piece copper exhaust gasket
3 layer cosmetic steel head gasket
Skimmed manifold and inlet
2” turbo down pipe
Straight through exhaust with centre exit DTM back box
Modified plenum for front mount intercooler and dump valve
Custom intercooler pipe work with blue silicone
Rover turbo intercooler
Thermex motorsport oil cooler
T3 base turbo with 38mm compressor, 360 thrust bearing, new core, adjustable -31 actuator, only covered about 2-3000 miles 250bhp
New silicone turbo oil drain
1” ¾ turbo carb, re built with new float spring and high boost needle
High flow Bosch fuel pump
New sender
Jack Knight straight gear box, newly re built with all new bearings
4 pin differential
Paddle clutch
Road/race release plate
Lightened fly wheel
Megajolt