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carby to efi..ej fuel system?

Posted: Mon Aug 06, 2007 8:14 am
by 98choppa
im putting ej22 in the Lseries..which had a carby.....not turbo.....

efi question....
i know i need to add a fuel pump somewhere........
does my car have sufficient fuel ,return etc...hoses for this?

thusss do i need a swirl pot under there....plus xtra return lines..?
ive checked out SUBARINOs album but thats an MY.....

any one give me some pointers?

Posted: Mon Aug 06, 2007 9:50 am
by discopotato03
If it were me I'd go to one of those you pull it style wreckers and find a late EFI car to rob for the fuel tank/fuel lines/pump and some pump wiring .
Generally fuel injected cars run larger bore fuel lines ie 6/8/10mm and EVERY hose on the pressure side MUST be propper EFI hose , low pressure carby hose won't cut it and is NOT safe .
I believe doing the factory tank and pump system gives good results and doesn't look aftermarket like the pre pump/swirl pot/pressure pump does .

Cheers A .

Posted: Mon Aug 06, 2007 2:24 pm
by El_Freddo
I've done the EA MPFI swap from a carbie job... My fuel lines work fine, as discopotato03 has said, all rubber fuel line on the pressure side has been swapped to the Injection rated stuff, but still run the smaller carbie steel fuel lines with no problems...

I'm yet to fit a surge tank, its probabily not really needed if you always run above the empty line on the highway, but if 4wding up hills etc, best to have one or the MPFI tank at least to avoid starving the fuel pump... starve it a few times and it'll be cactus...

Basically the fuel pump you will need (VL commodore fuel pump) bolts straight in where the standard one goes. If you want to run a surge tank:

- keep the standard fuel pump
- mount the surge tank where you're happy with it (under bonnet okay? i dunno about this)
- plumb it all in properly (EFI pump draws fuel from down low -but not from bottom, don't want any bits of crap being picked up-, return line FROM engine up high as is return line TO fuel tank, and the FUEL IN from standard pump somewhere in there too.
- mount the EFI pump nearby or under bonnet if this is okay to do - use wiring from the EFI loom to run efi pump - put a kill switch in the line too - added security and doesn't allow the pump to dry run while surge tank fills...

Other than that have fun, someone will know about mounting surge tanks and fuel pumps under the bonnet and if its okay to do.

Cheers

Posted: Mon Aug 06, 2007 2:35 pm
by BlackMale
As discopotato03 Said there is a massive difference between the return lines and even though El_Freddo has his running without the EFI lines I was not prepared to chance it (I am currently in the process of changing mine over) and would not recomend it.

Just be aware that if you do decide to change the lines that it’s a big job due to their location (heaps of stuff has to come out to get to all 3 lines). The pick a part option suggestion would work however tell the blokes what you getting I reckon cause it going to take you some time to dismantle it all.

Enjoy the build either way though.

Posted: Mon Aug 06, 2007 2:51 pm
by El_Freddo
BlackMale wrote:As discopotato03 Said there is a massive difference between the return lines and even though El_Freddo has his running without the EFI lines I was not prepared to chance it (I am currently in the process of changing mine over) and would not recomend it.
In my defence of leaving the standard carbie steel fuel lines:

I don't see what the problem here is... these are metal lines that you are talking about... everything else is EFI rated. The carbie steel lines are smaller in diametre, i'm not running a high performance engine so i don't see the need to up-grade these lines for higher fuel volumes to the engine...

End.

The lines you need to move if you go the MPFI diametre size run down the left hand side of the car, coming into the cabin space beside the passenger seat below the door. Remove all the floor lining and you'll see them, might help to move the passenger's seat too...

Cheers

Posted: Mon Aug 06, 2007 3:28 pm
by 98choppa
beauty....!
heres the scenarios i got in mind with help from you guys--

1 * vl commodore pump in place of Lseries standard lil' pump (this is a lil'cube about 2" big?????)
* use efi hose from there to the std steel fuel liine
* change to efi hoses in engine bay --to efi filter --to engine fuel rail --to L series steel return pipe-- what about efi hose to standard return line in the tank?

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2 * keep L series pump where it is
* retain standard lil' filter there and fuel lines up to steel line
* in engine bay mount swirl pot and h.p. pump close to feul rail
* use efi hose --to efi filter --to fuel rail --back to upper swirl pot -- also swirl pot returns to Lseries return pipe-- standard fuel return hose?
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Q..(does that lil' Lseries pump make enough pressure to feed that swirlpot? i put me ear up to it and it just clicks along doesnt it...?)

Posted: Mon Aug 06, 2007 9:20 pm
by steptoe
A neat fuel supply line option is copper pipe as used in LPG applications, so pressure wise safe for efi, available in different sizes, or used to be anyway, coiled 5 or 6m lengths and comes sheathed with power/earth wires to rear. Just secure it merrily along the way underneath.

Posted: Thu Aug 09, 2007 4:04 pm
by 98choppa
ok peeple ive held up the vl pump under the car...that looks easy...

now.... im thinking i should put the bigger return pipe(brass.yeh?) for an ej22 because its only about 3...4 mm pipe now?!?!

this pipe goes into the front of tank at same place as the fueloutlet?!

where will i return bigger fuel line to?? do i have to go round to the filler neck or something?

im almost thinking ill swap the vapuor pipe----return pipe cos thats bigger
any quams with that??? ill still have to link it to the filler neck i guess

seems so complicated but so easy......bla ..... what do yall think????

Posted: Thu Aug 09, 2007 8:58 pm
by timmo
I'm using the vapour pipe as the return like you said, was too lazy to swap fuel lines from efi car. Just silver soldered up some reducers. No probs so far!

timmo

Posted: Mon Aug 13, 2007 9:11 am
by 98choppa
hey timmo. question..s.

so youre using that larger pipe running up the car for fuel return?(-was vapour pipe)

what happens when it gets back to the tank??? are you still entering the tank via the small return fitting (next to the "out" hose)?

does that really make it worth upsizing the pipeline anyway?.. am i just as well to use the smaller return pipe all the way up the car??

cheers

more question....if i put my vl pump where the std pump was do i need to retain the lil' module just after the the pump
(i think its a valve or som......?size of a mushroom )is there a certain type to put there for efi --highpressure side

Posted: Thu Aug 16, 2007 2:45 pm
by El_Freddo
Choppa,

I've used all the original steel lines as they are in the car, without changing the original use of these lines... eg the to engine line is still the to engine line, the vapour line is still the vapour line. I didn't see the need to change these around.

Must stress though, all rubber hosing has been changed to EFI rated stuff where it needs to be changed.

Cheers

Bennie

Posted: Thu Aug 16, 2007 4:55 pm
by timmo
98choppa wrote:hey timmo. question..s.
yeah i'm using the vapor line, but i'm using an efi tank so its got a heaps bigger return than the carby L series one. I still need a reducer though coz the vapor line is actually a tad smaller than the tank inlet. I dont really know if it would be worth using the larger line when the tank inlet is still tiny in your case.

timmo

Posted: Wed Aug 22, 2007 12:11 pm
by 98choppa
ok im going to stick with the standard small return pipe too

as per diagram(subarinos surge tank plan)ill use high pressure hoses to engine
but low pressure ones to return to tank----------ok????

Posted: Wed Aug 22, 2007 5:04 pm
by timmo
you still should change the return hose sections to high pressure type

timmo

Posted: Wed Aug 22, 2007 6:29 pm
by Matatak
timmo wrote:you still should change the return hose sections to high pressure type

timmo
thats really not necessary actually
u can do it if u want to fork out the extra heap of money for that length of high pressure hose but im not bothereing

Posted: Wed Aug 22, 2007 7:36 pm
by timmo
that length? 1 meter would pull it up.... its only to replace the hose sections that are there. I certainly wouldnt trust 20 year old neoprene hose.

timmo

Posted: Wed Aug 22, 2007 8:39 pm
by Matatak
werent u talkin bout from the engine return line back to tank
or is he puttin in a surge tank

sorry read this awhile ago havent refreshed myself with it