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Ok so im doing the ej convert and im planing to use a surge tank, so how do i set up the fuel delivery system?

Carby pump to surge tank, surge tank to efi pump, efi pump to engine, engine to surge tank, surge tank to main tank

or

remove carby pump and replace with hose to use a pick up, from tank to efi pump, pump to surge tank, surge tank to motor and from engine back to main tank?

Cheers,
ian

Provided your low pressure pump can pump as much fuel as the injectors inject at full noise your fist method will work .

The second method won't work at all.

Basically what you're trying to achieve in an EFI system is a pressure zone between the EFI pump and the regulator at the end of the fuel rail. You want adequate fuel pressure and flow to suit the injectors.

If you're using a surge tank this would be my recommendation:
Use a decent aftermarket carby pump to supply the surge tank, something along the lines of a Facet Red or if the budget allows a Holley Blue. If neither is available get an electric pump capable of running a carby small block V8. Mount the surge tank in the rear close to the tank, this will help prevent gas buildup. Mount the EFI pump as close as possible to the surge tank, and if possible lower than it. This will help supply the EFI pump with plenty of fuel, which is the whole point of the surge tank .

So basically your system should go: tank; low pressure pump; surge tank; efi pump; line to engine bay; fuel rails; regulator; return line; surge tank; fuel tank. I shouldn't need to mention that apart from the EFI supply outlet all outlets on the surge tank need to be at the top.

Just to throw another thought in, is it possible to use an L series EFI, 4wd tank ? then just run a big ej pump like a bosch 910 or walbro ?

The L series EFI system is perfectly capable of running an NA EJ in stock form. I've even seen EJ20G's run on EA82 MPFI fuel pumps.

I am looking into this for an ej20T, just would like 1 tank and 1 pump, not multiple of everything that can fail (and have to pay more money)

i'm running the stock L-series pump to supply the surge-tank and then a walbro 255lph from the surge-tank to the ej20t and back to the surge-tank... works fine...

im running an ej22

stock MY pump from fuel tank to surge tank in the engine bay,
efi pump from surge tank to fuel rails.
fuel rail return back to the surge tank
and surge tank return back down the breather line to the fuel tank

seems to work fine

Ej20 N/A,

Tank
to
EFI filter(VN commondore)
to
EFI Pump(VL Turbo)
to
Motor
to
Tank.

Pump and filter are under tray(origanal location).
Working fine but i wouldn't try this with a Turbo motor.
Daza.

Daz, you should swap the order you have running now. Tank > standard filter > EFI pump > EFI filter.

That setup works fine with a standard EJ20. More boost and/or power and you need to run a surge tank as close to the fuel rails as possible.

Any one fitting an EFI pump to a non efi car needs to know that ALL fuel hoses between the pump and the fuel rails on the motor need to be EFI grade fuel line. The return line can be standard grade fuel line.

So i dont even NEED the surge tank?

thats what i thiught originally... worked perfectly well with the ej22 without a surge tank

then i did some off roading and anything less than half a tank of fuel and i had real trouble keeping the engine full of fuel

after the surge tank went in... no trouble what so ever

I am using a surge tank in my N/A EJ20 into coupe. The main reason is the VL commodore inlet on the pump is a 1/2" fitting. On an MY fuel tank is only 5/16".

The guys that fitted commodore pump without a surge tank what was the size of your inlet to the pump?

Is there an EFI pump that has a 5/16" inlet and outlet that would suit a 2L EJ conversion?

Generally all pumps from bosch have a half inch fitting.

85wrx wrote:Is there an EFI pump that has a 5/16" inlet and outlet that would suit a 2L EJ conversion?

The EA82 MPFI pump should do the job for just about any NA EJ.

Jordan.

Im planing on using a bosh 044 or VL turbo pump
i think ill go with a carby pump for a v8(as sugested) maybe a holly blue, to the surge tank then use the o44 or vlt pump up to the engine

is the brumby pump in tank or no?
to have a return can i just drill a hole in the pick up in the tank and braze a fitting into it?

85wrx wrote:The guys that fitted commodore pump without a surge tank what was the size of your inlet to the pump?

from memory...
Tank outlet is 5/16"
Filter is 3/8"
Pump inlet is 1/2"

Daza.

i am doing an ej22 swap into my 79 and i'm wondering about the same thing...

why do you need a return line from the serge tank to the fuel tank? won't the pressure from the serge tank being full stop it from pumping just like a float bowl stops the fuel from coming into the tank? i'm really not sure on this one... one part of me says it should be fine... but the other part of me is saying that there will be a huge pressure build up in the serge tank if there is no place for fuel to go... but if you have a return line to the fuel tank then won't the carby pump be going full blast all the time? i know with the 79 pump is wasn't to happy just freewheelin when i was draining the tank...

or... could i just install a normal baffled fuel tank in place of the stocker? and what pumps are you guys using? i always see people using walbro pumps on the wrx's and such but those are all internal pumps are they not? would you have it in the serge tank or outside of it???

anybody got pics or a pretty diagram? i've always been better with pictures...

thanks!

When pricing up a pump be careful that the parts store is not inflating the price for a "turbo" part. The replacement VLT pumps are the same as regular VL pumps yet some places charge nearly twice the price for it. The Bosch part number is 0 580 464 070 if anyone needs it.

VL400 wrote:When pricing up a pump be careful that the parts store is not inflating the price for a "turbo" part. The replacement VLT pumps are the same as regular VL pumps yet some places charge nearly twice the price for it. The Bosch part number is 0 580 464 070 if anyone needs it.

Cheers man