After reading numerous posts regarding fuel pump upgrades I've decided on using an under car mounted suction fuel pump. This necessitates modifying the existing factory fuel pump housing to accept larger lines and different pickup and return sizes and locations. We know that by increasing our HP beyond certain levels requires the addition of an inline pump or sumping the tank. I prefer to do neither. I also prefer not to have to go into the fuel tank again. My pump of choice is a Weldon. They will feed properly, mounted above/below the tank (self-priming).
They are not inexpensive, but with the money we invest in turboing, as well as other system upgrades, to me a worthwhile investment.


Pictured on left is a Weldon model 2025, flows 550 lph, @72psi, draws 18.6A, will
support 1400hp fuel injected. On the right is a model A2005-A 275 lph @72psi, draws 8.6A, will support 650hp fuel injected.

There has been some discussion regarding factory fuel line sizes. Here is a picture showing some various size lines ranging, from left to right, -10,-8,-6, OEM pressure line and OEM return line.



All that's being done with this housing is we're cutting some plastic, drilling some holes larger, and bonding in some Aluminum tubing with fittings.

Picture of un-modified housing

Picture of modified housing (not completed)


The following tools were used. Dremel with cut-off wheel and drum type sanding belts for the Dremel. Drill with bits appropriate for tubing diameter and an inexpensive tubing bender. Materials consisted of tubing size of choice(Aircraft Spruce and Specialty) tube/AN fittings (Summit Racing)(these are compression by AN, flared fittings would take up to much room) a piece of rubber fuel hose (in this case bcuz I didn't have any pieces long enough on hand)hose clamp, and a 2 part epoxy with flox added. Flox is flocked cotton fiber added to an epoxy matrix for structural strength.


First step remove pump (per manual) remove float, filter, fuel pump, rubber hose from pump to plastic fitting, metal flange and rubber gasket.


Before

After

In this case, due to the size of the -10 lines, it is necessary to swap out the factory positions for the lines. pressure becomes return, return becomes pressure(or in this case suction to the pump)Suction line is closest to center.

A channel to accomodate the return line needs to be cut out of the left side of the housing. The dremel with cut-off wheel was used and smoothed out with the drum sanding belts.The black plastic piece of tube that the fuel pump hose connected to is removed and will be sealed with epoxy/flox later.


Tubing is formed for 90" angles with overhang kept to a minimum to facilitate installation in factory opening. Fittings are attached.









Since I was short of a sufficiently long enough piece of tubing I am bonding in two pieces for the return line and connecting a piece of hose for the suction. The channeled out section of housing will be coated with epoxy/flox and the tube will be bedded in this and then sealed to the other piece (just buy a long enough piece)
The suction line will be bonded in place and the OEM fuel tube will be sealed as well. Locations where tubes pass through housing are sealed with eboxy/flox. Important note make sure fitting orientation is scribed for location prior to bonding.
i.e. ability to access 8mm bolts when re-installing housing and making connections to hose. A zip tie was installed to keep the hose in place(wouldn't had to do that if I had longer tubing) The suction line should be approx. 9-1/4"-9-3/8" long measured from the plastic flange. Keep it level with the float in the down position for adequate pickup at low fuel level. The return is placed slightly higher to minimize any potential interference with turbulence from fuel returning on the float's sensing.


Finally, the connector for the sending unit needs to be modified to be able to lower
the fitting. It was cut down and potted in place. One line's orientation had to be right over the connector. A suitable connector will be installed between factory harness and housing.


The car will use -10 Stainless Steel hose from the fuel pump housing to the fuel pump and the return, as well, to the area of the fuel pump. The -10 will transition to -8 hardlines under the car in the factory location then further transition to -8 Stainless Steel hose in the engine bay.

The factory fuel/brake line cover was removed, the plastic brackets securing the fuel/brake lines were rotated down and the plastic clips securing the fuel lines were ground down with the dremel sanding drums allowing the placement of the -8 hardlines. The -8 hardlines were additionally clamped with MS clamps for -8 tubing.




I am waiting on additional fittings and hose prior to mounting and wiring the pump.
An inline filter and shutoff valve will be mounted prior to the pump easing the filter replacement with possibly an additional inline filter in the engine bay.

 

very nicely done !! i sometimes wish i woulda stuck with the factory tank.

 

great write up for the high HP guys =),

 

Thanks for writing this up Pat I hope to tackle something like this next winter.

 

Nice work bro
So this is where the fuel pump assembly of my old baby went to

Marcus

 

yep

 

awsome write up an great for keeping oem tank

i just went with a whole new fuel cell and lines and sump.... pain in the ass to make fit in the rear of the car but i love it it even takes 5 more letres then stock of fuel

 

AWESOME WRITEUP! I have been trying to decide which way to go... Fuel Cell... Sump'd Stock Tank... Inline Booster pump... Surge Tank... this way looks the best to me so far and most likely cheaper! What do you estimate the whole project cost? I.E. Parts needed to modify the stock fuel unit and the lines / fittings ect? Just an estimate so I know what I'm getting into... Thanks and keep posting I am VERY INTERESTED IN THIS!

BOOKMARK!

 

The cost so far to convert to a suction (out of tank) fuel pump so far,

The 3 models of pump most applicable to our car are as follows:

1) A2005A ( specs in first post ) cost new $590.00 used $4-450.00
2) A2015 387lph@72psi 11.75A cost new $679.00 used $4-475.00
3) 2025 ( specs in first post ) cost new $729.00 used $4-600.00

inline billet filters $40-80 depending on brand micron range AN size

Fittings: All fittings were purchased from Summit racing under their brand name and the Earl's brand.

1) housing fittings (2) EAR-165010ERL tube adapter -10 male $34.78
2) hard line fittings (3) SUM-2200078 -8X1/2" male tube adapter $24.00
hard line fitting (1) 165106ERL -8 fem to 1/2" tube $9.25
3) -10 hardline 3' Aircraft Spruce 5/8 by .035 wall $6.00
4) -8 hardline Aircraft Spruce 2 pieces @ 6' 1/2" by .035 $19.68
5) MS21019-WDG8 clamps $2.76
6) -10 AN hose to Fem -10 (4) SUM-220087 $64.00
7) -8 AN hose to fem -8 AN (4) SUM-220890 $28.00
8) Reducer (1) SUM-220045 male -10 to male -8 (return line) $6.88
9) SS hose 6' -8 SUM-230806 $26.95
10) SS hose 6' -10 RUS-632160 $37.95
11) Peterson Fuel S/O valve -10AN Male to -10AN Male $107.00
12) coupler S/O valve to filter EAR-915110ERL -10AN FEM to -10AN FEM $8.95
13) coupler filter to pump EAR-935110ERL 90" -10AN FEM to -10AN FEM $17.95
14) Epoxy 2 part I have a bunch on hand you don't need that much
get something that has a higher viscosity longer pot life.
15) Flox Aircraft Spruce 1 lb. bag ( we could do everybodies housing) $3.95
16) My pump $450.00


Total about $850-900 with a used pump plus a relay, wire , and maybe a couple of other fittings depending on placement.


I'm selling the brand new A2005A with filter. Look in for sale

 

Being the moron I can sometimes be I neglected to check for continuity (a good electrical fit) between the connections prior to bonding I just
ASS"umed that it was there. So after drilling out the epoxy and removing the connector I decided there is an easier solution. Number one cutting that connector down was a pain and if you slip with the cutoff wheel, a bigger pain.

buy some female pin connectors at radio shack. I had some round female ones around so I used them.


The male pins in the housing are a blade type and you may be able to buy that kind as well.

The round female receptors have a slot running lengthwise down the connector
so they will expand enough and fit tightly around the pin in the top of the housing.

I have opened one up for clarity


These are typically crimp fittings. Since we don't want to do this again get a soldering iron and solder the wires on, or use the proper crimp tool, then bend the tabs over.










Finished unit, you won't have as much epoxy on the left side as this if you use the longer one piece tube but it will still work as good.







Pictures out of sync but


You know I've got continuity now. After checking for good contact then you bond them in