Dual Fuel Pump How To

3mi from the end of the Team O'Neil rally we had a complete fuel pump failure.

It was suggested that most Rally cars have a dual fuel pump setup.

My impression is that this should be a fairly simple thing to do and an opportunity to bring the pumps out from under the car to inside and in the trunk.

What I'm thinking is a couple of 'Y' connectors, a switch, a relay and a bunch of wire ?

I was on 034 site and saw a kit for dual fuel pumps (looked like a miny fuel rail) intended for both pumps operating at the same time. Guy said I needed a hefty check valve if I wanted to use that since there might be leak-down into the non-operating pump.

Would I have the same situation w/the 'Y' connectors?

Thanks,

V-

http://www.rallyrace.net/view/?2004-06-26/fuel_supply_done.jpg

http://www.rallyrace.net/journals-2004.php

Scroll down to June for a little picture. I'm sure JV or somebody will show up with an explanation soon enough.

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Andrew Steere
Lyndeborough, NH
KB1PJY

Thanks for the reference Andrew!

My question at this point is if the circled items are just 'T' fittings or if they are also check valves?

vbares Wrote:
-------------------------------------------------------
> Thanks for the reference Andrew!
>
> My question at this point is if the circled items
> are just 'T' fittings or if they are also check
> valves?

just Ts muchachito, easy. Why did pump fail? Dirt? heat?

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John Vanlandingham
Sleezattle, WA, USA

Vive le Prole-le-ralliat

www.rallyrace.net/jvab
CALL +1 206 431-9696
Remember! Pacific Standard Time
is 3 hours behind Eastern Standard Time.

don't know yet. Haven't crawled under the car - although my curiosity is getting the better of me.

In the corporate life, they say you have vacation time and weekends - but in actuality - stuff piles up while you're away - then the family, etc...whine, whine, whine ;P - I know STFU and get on with it!

In any case I'll soon find out what happened - will let you know. Seems like a simple (like that) implementation from the pics and I should be able to use the stock Audi parts - btw, how much do those Walbro pumps go for (Audi wants $200-$300 for one).

V-

We built a nice little dual setup after having a fuel pump failure. It utilizes two walbro pumps that were about $100 each.
I could potentially build some more of the distribution logs for people if there is interest.






-Luke

Hmm - that seems about right.

here's a link to the 034 stuff:
http://www.034motorsport.com/product_info.php?products_id=219

The stock audi stuff doesn't have a fitting for the inlet, just a pipe to clamp the stock rubber hose to. I really am not interested in a fuel cell at this point, given that the fuel tank is inside the car and not in danger per se.

you can email me with your thoughts on what you thing you could build

vbares aht verizon point net

that's awesome

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Andrew M
Onterrible
30ish

Hey JV:

1. The pump did not fail - broken wire
2. Now that I know dual pumps is a good idea - I feel compelled to implement it.

In your implementation - it looks like you're using a combination of NPT and AN fittings.

From my reading AN = better seal (straight threads + O-Ring), but $$ and NPT = thread seal required, thread binding seal and relatively inexpensive.

Are those T's NPT ?
What are you using at the hose ends - they seem pretty different from other implementations I've seen.

Currently I've got SS inside the car - lots of it Considering replacing w/hard lines and using all that SS as you've done for the dual pump assembly and also in the engine compartment. What are the pro's and cons of having hard lines vs. SS lines inside the car?

How those parts coming along - in the post yet ?

thanks,

v-

Any plumbing differences for a carbed setup?

Those Whinebros are impeller pumps if I recall correctly ,most of the low-pressure carb pumps are diaphragm pumps.

Just wondering if you need to worry about whether the non-running pump will allow fuel to flow through it backwards.

Cheers, Ted

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Pure mathematics is the enemy of every truly creative man -- Sir Alec

Ted Andkilde Wrote:
>
> Those Whinebros are impeller pumps if I recall
> correctly ,most of the low-pressure carb pumps are
> diaphragm pumps.

The crappy rattlebox pumps may be diaphragm pumps (never looked, just tossed 'em in the trashcan) but *good* carb pumps are impeller type.

Well, I should say *high flow*... I have seen a number of awesome killer boutique pumps where they ran STEEL vanes in an ALUMINUM housing... lasts for a little while but eventually the vanes win! And send a bunch of aluminum into the carb in the process.

> Just wondering if you need to worry about whether
> the non-running pump will allow fuel to flow
> through it backwards.

EFI style pumps have check valves to prevent pressure loss after shutdown, so when you come back to your car after eight hours it lights off quickly. I don't recall ever seeing a check valve in a carb type pump.

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Pete Remner
Cleveland, Ohio

1984 RX-7 (rallycross thing)
1978
Silence is golden, but duct tape is silver.

Pete Wrote:
EFI style pumps have check valves to prevent
> pressure loss after shutdown, so when you come
> back to your car after eight hours it lights off
> quickly. I don't recall ever seeing a check valve
> in a carb type pump.
>
>
>
> Pete Remner
> Cleveland, Ohio
>
> 1984 RX-7 reshell
> 1978
And when you buy the zoot-capri pump to run 400 bhp Cossies and you see the size of the holes in the back-flow valve, you know that you want to eliminate it.

---

John Vanlandingham
Sleezattle, WA, USA

Vive le Prole-le-ralliat

www.rallyrace.net/jvab
CALL +1 206 431-9696
Remember! Pacific Standard Time
is 3 hours behind Eastern Standard Time.