fuel pumps

wrx_nut · Post by **wrx_nut** » Thu Mar 15, 2007 5:22 pm

ive heard of people running an ea82 carby type fuel pump that feeds the ea82t type fuel pump...are there any benifits? or is it just to supply a surge tank....?

wrx_nut

timmo · Post by **timmo** » Thu Mar 15, 2007 6:46 pm

is yours playing up?

wrx_nut · Post by **wrx_nut** » Thu Mar 15, 2007 7:13 pm

na just a question...

wrx_nut · Post by **wrx_nut** » Fri Mar 23, 2007 7:24 pm

so whats the go? anyone got a comment?

daza · Post by **daza** » Fri Mar 23, 2007 7:48 pm

wrx_nut wrote:ive heard of people running an ea82 carby type fuel pump that feeds the ea82t type fuel pump...are there any benifits? or is it just to supply a surge tank....?

wrx_nut

Yeah just to supply a surge tank...
and sometimes using a BIG fuel filter instead of a surge tank, particully in N/A convertions.
Daza.

discopotato03 · Post by **discopotato03** » Sun Mar 25, 2007 10:53 pm

Lift pump swirlpot systems work like this .

Low pressure lift pump fills the swirlpot only and any extra is returned to the fuel tank .

EFI roller cell pressure pump draws fuel from the swirlpot and sends it forward to the fuel rail , the unused portion is returned to this swirlpot .

A lot of fuel goes round in circles between the pot-EFI pump-return to pot . As long as the lift pump can move more fuel than the injectors are injecting the system will work in regulation . If it can't the level in the pot will drop and eventually starve the pressure pump .

No one tries to feed the pressure pump directly from the lift pump and very few can move sufficient volume to do so . Even if they could it would defeat the purpose of having the swirl pot because its only there to give a constant supply for the EFI pump . Its a way of getting around not having a fuel tank designed for a fuel injection application . With a carburettor its not a problem if the fuel pickup in the tank is temporarily robbed of fuel (low fuel and surge in fuel tank) because it has a reserve in its floatbowl . When this happens to an EFI system fuel pressure rapidly falls and the engine starves because there is little fuel pressure to push fuel through the injector valves .

Even doing it this way you can at times have problems with the fuel in the pot getting very warm because a lot of it is doing continuous loops between
the pot and the warm fuel rail/engine bay . I believe this problem can be got around by using another EFI pump as the lift pump because it can cycle much greater volumes of cooler fuel between the fuel tank and the pot .

Julian Edgar who was the original tech editor for Zoom wrote an article about this aeons ago (write up was called Pot Pourin) and his system works .

Cheers A .

brumbyrunner · Post by **brumbyrunner** » Mon Mar 26, 2007 10:21 am

Make sure you're EFI pump is not oversized either. Otherwise you'll just warm the fuel faster.

discopotato03 · Post by **discopotato03** » Mon Mar 26, 2007 11:55 pm

Very true , a Bosch VL Turbo EFI pump will be more than enough in most cases and readily available . Deleat ALL notions of Bosch 975/984/044 pumps because they create many more problems than they solve in this case .

Cheers DP03 .

buddah · Post by **buddah** » Sun May 25, 2008 12:56 pm

discopotato03 wrote:Deleat ALL notions of Bosch 975/984/044 pumps because they create many more problems than they solve in this case .

What about for an ej20t? I've got one of those 014's and it's real noisy and annoying. Sounds like it's on it's last legs too. I was told to upgrade to an 040 or an 044. Or would it be easier just to go with the vl 070?

YouTube · Post by **El_Freddo** » Sun May 25, 2008 10:28 pm

discopotato03 wrote:A lot of fuel goes round in circles between the pot-EFI pump-return to pot . As long as the lift pump can move more fuel than the injectors are injecting the system will work in regulation . If it can't the level in the pot will drop and eventually starve the pressure pump .

And kill it - doesn't take long to kill an EFI fuel pump when its trying to pump fuel thats not there!

discopotato03 wrote:Very true , a Bosch VL Turbo EFI pump will be more than enough in most cases and readily available . Deleat ALL notions of Bosch 975/984/044 pumps because they create many more problems than they solve in this case .

Or a VN 5 litre V8 external fuel pump will do the same job and cost you less than the VL turbo pump... I dunno if its any of the bosch models mentioned above.

buddah wrote:What about for an ej20t? I've got one of those 014's and it's real noisy and annoying. Sounds like it's on it's last legs too. I was told to upgrade to an 040 or an 044. Or would it be easier just to go with the vl 070?

Some EFI pumps are noisy. You know when they're on their way out when they make nasty noises and need a knock to get them started

Just ask some of the WA crew about my pump and its antics

Cheers

Bennie