efi to carby fuel system

[DANNY8]

My VK wagz is running a VL fuel tank, VR intank pump and return line as we converted it to EFI. Now gonna go carby for a while, so what would be the best way to get the fuel up to the motor?

I don't wanna rip the whole lot out. Can I just keep using the EFI pump? I'm using a Barry Grant return reg (for carby), but is that capable of running with so much pressure through it? Or will I have to change to a smaller carby fuel pump? If so, can I just use a VL intank low pressure pump, to feed an external Carter Black or sumfin?

Any ideas?

[ari666]

NAAAAHHHH MAAANNN!!!

lol. AFAIK you can get either a 0-15psi reg (carby) 10-45psi reg and efi regs (100ish) 10-45 is too much for holley or quaddys even if you tweaked it right down, itll still push past your needle/seat

of course im willing to be wrong, just stick a mechanical pump on it!

[DANNY8]

The reg I have I assume is a 0-15psi reg. So can I use that and set it at say 6-7psi? If there is 45psi coming at it from the EFI fuel pump, will it still work sufficiently using the carby reg? I don't want to run extreme fuel pressure, it's just the EFI pump is already in there, and as I will be changing back to EFI in a month or 2 I don't want to swap it all over unless I really have to.

[ari666]

yeah i was speaking to a guy at VPW about this when i was looking at fitted the 454 with a carby (to keep costs down till i could afford to go full efi) he said that the 0-15 holley reg wouldnt be able to cope with the 115psi pump i would need for EFI. he reckoned the seals in the would crap out and it'd end up dumping too much pressure in eventually.

whether he said that to make a sale of a 120 buck carter black pump, im not sure. either way i decided not to do it. i would be dead keen on knowing if that reg could cope, cos then i can start messing with my fuel tank while still running the 327.

my plan was a bosch 044 with a surge and return. one thing i did wonder though was: what would happen if i just put a splitter on? i.e. a t piece where the fuel line runs straight to the reg and in the same fitting runs the return line. surely all excess pressure would just feed back to the surge?

[DANNY8]

What if I run a VL low pressure internal pump, which feeds a Carter black....I guess that would work.

I don't wanna run a mechanical pump. I'm over them....and I'm not even sure if the cam has a fuel pump eccentric on the end of it, as I built it for EFI.

[ari666]

ah yeah. that would be a bit of a problem...

those VL intanks are pretty gutless. think they are only around 4psi. you dont need a pump in tank for a carter black, you just install it below your tank. i.e. assembled to one of your tank straps.

[DANNY8]

But then I still need a sender to fit the EFI tank. If I use carby sender with no pump, just the pickup tube, will it fit inside the EFI tank?

[Not_An_Abba_Fan]

Use the EFI pump with a good regulator with the return line and it should be fine. Holley do one Holley Performance Products Two Port 4.5 - 9 PSI Bypass Style#12-803BP

[*uwishn*]

hey mate did you ever have the engine problem like my self and nasty1 did?? (idling bad,running like it was down on a cylinder)

[ari666]

hmmm, not sure. they are very similar shape and size. i thought they were identical except later models had the filler tube affixed with a rubber joiner and VK/VL etc were soldered onto the tank...

you can use the carter with the efi pump still inside the tank. my intake died and i didnt ever bother taking it out of the tank, just cut power to it.


i think i may now be getting very confused.

[DANNY8]

Well I might just give it a crack using the reg and see how it goes.

Here's a pic of it...haven't got a close up. The whole fuel system in the pic come off a carby 355, and got it for me other wagz, but just using the fuel log and reg on this donk for a few burnout comps. I guess it'll either work or it won't lol....one way to find out.

[DANNY8]

hey mate did you ever have the engine problem like my self and nasty1 did?? (idling bad,running like it was down on a cylinder)

Yeah the old EFI motor in the wagz seemed to have a miss on idle, but cleared up as soon as the foot went down. Still not sure what it was. Built a new motor for the wagz, and the EFI motor out of it we're putting into a GQ Patrol shorty, but gonna rebuild it anyways. I still rekon a valve was dodgy, will check them out when we rip it down.

[drewVHSS]

My VK wagz is running a VL fuel tank, VR intank pump and return line as we converted it to EFI. Now gonna go carby for a while, so what would be the best way to get the fuel up to the motor?

I don't wanna rip the whole lot out. Can I just keep using the EFI pump? I'm using a Barry Grant return reg (for carby), but is that capable of running with so much pressure through it? Or will I have to change to a smaller carby fuel pump? If so, can I just use a VL intank low pressure pump, to feed an external Carter Black or sumfin?

Any ideas?

Intank low pressure pump may be good enough to run it by itself.
The VL 6 cyl internal pump is the same part number as the intank pump on VK brocks and VL carby fed 308's. Put your original VL internal lifter pump back in and you'll be ok for a stock motor as i've seen heaps of the later carby vl's have only the internal pump. You could also chuck on an early timing case cover and use a mechanical pump for a while. My VH SS only uses a factory high volume mechanical pump and my motor is far from standard, no fuel starving issues either.

[Westie]

Might need a large return line if your going to overload the reg, pushing 40odd PSI into reg and only 7 coming out the other side.

[ari666]

Intank low pressure pump may be good enough to run it by itself.

i disagree. my VK internal caused me all sorts of problems which i only figured out once i finally got rid of it.

[DANNY8]

Might need a large return line if your going to overload the reg, pushing 40odd PSI into reg and only 7 coming out the other side.

Even on an EFI setup, most of the fuel is going back to the tank anyways, it just needs more pressure in the rail. So the fuel going back to the tank should be similar whether it's EFI or carby.

[DANNY8]

Ended up swapping the high pressure EFI intank pump for a VL intank low pressure pump, and that feeds a carter black (14-16psi), the reg is set at 5-6psi, and so far it's been working good as far as I know.

[ari666]

yeah i was thinking about that the other day. if you stick a holley fuel reg, even though it has two fittings, one is NOT a return line. if you restrict the pressure to 7 or 8 psi, then BOTH the outlets are running on 7-8psi.

just sayin'