trangk

Anyone here running dual walbro in tank pumps? If so, how did you do the wiring and mounting? I'm finding it to be a VERY tight fit with the pumps having to sit in the slosh tray in the tank. Also the wiring seems straight forward, but did anyone upgrade the stock wire size in the tank? If so, how did you do that?

Pics would help

SCoupe

Probably best answered on the Supraforums.com Search "dual pumps" many hits, with pix, a good example: http://www.supraforums.com/forum/sho...ght=dual+pumps

From supraforums member Morefaster, (I take no credit for this): "Run 8ga wire to a distribution block in the hatch area. (Using two bosch 5 wire relays) Apply +12v via individually fused lines from the distribution block(optional you don't have to fuse them seperately) to pin 30 on each relay. Ground Pin 86 on relay 1. Connect pin 85 of relay 1 to pin 86 of relay 2. Connect relay 2 pin 85 to the output of the fuel pump ecu (Blue with red stripe *this wire should be cut so it no longer runs to the pumps, only to the relay). Connect relay 1 output #87 to the + side of pump 1. Connect relay 2 #87 to the + side of pump 2. ground both pumps.
Note***Pin 87a is not used

There is definately more than one way to wire dual fuel pumps, but this is one effective way and happens to be how I wired mine. This will support dual TT pumps or dual walbros."

USAF_RT

I am also very curious about the mounting...since the Supra guys have their 2 and 3 Walbro hangers...what do the SC guys do?

motorheaddown

I'm running dual pumps, and I've attached them to the OEM hanger. One pump sits where the OEM pump used to reside (duh ), and I strapped the second pump to the first using steel worm gear straps.

To keep the pumps from making obnoxious "humming" sounds while in operation, I used two strips of 1/2" wide, 3/16" thick, 3" diameter fuel filler tubing (obviously fuel proof) to insulate the pumps from one another when strapped together. The rubber strips are used around the second pump; the worm gear clamps are applied around the rubber strips to hold the second pump to the first pump.

The pumps sit in the slosh tank at a diagonal (the second pump is at the 2 o'clock position) with both filters pointing towards the rear of the tank.

As for the wiring, I drilled an extra hole through the access plate, filled it with epoxy (so it won't conduct electricity), and drilled a hole through the center of the epoxy using a headless screw. I then use two, very thick, nylon washers on both sides of plate to insulate the +12v lead of the second pump which is bolted in place with a screw from the inside.

If I could change anything, I would have moved the pumps to the very back of the slosh tank with the filters pointing forward. When I'm low on gas, the pumps will suck air under very hard acceleration.

-scott

Supra Dr

iTrader: (14)

Scott,
Heres a noob question from an OG reguarding the actual fuel line routing.
On the supra dual line mod everyone runs the lines out of the top of the
hanger asm. Just like the factory did, the second line just follows the same
routing next to the stock line.
On the SC the tank is basically in the truck & all the lines exit the bottom
of the tank. So, whats the accepted method of routing the 2nd line out of
the bottom of the tank?
On my car I gave up & went external. I removed the L.R. fitting on the
bottom of the tank & installed a -12AN bulkhead fitting. If I ever wanted to
go dual/trip in tank I can Y them together in the tank & out the -12AN.
But, I'm thinking there's a easier way. (I had remove the tank, clean it &
purge any fuel vapors before drilling)

https://www.clublexus.com/gallery/sh...0&ppuser=13123

vntperform

iTrader: (15)

Bringing this back from the dead...

Wow, Supra dr thats a hell of a fitting!

motorheaddown: My setup is very similar to yours, I did the same thing as you did with the pumps and I isolated each so they wouldn't cause interferance to each other.... but mine are sitting next to each other in the tank, and in the slosh area, just like OEM.

I drilled a tiny hole into my hanger's hat and ran my wires through for pump#2 and then beaded some silicone into the hole so the wires won't become frayed, and so fuel vapor wouldn't escape. I also reused the stock feed line for pump#1 and then drilled a hole on the hat for a -6 bulk head w/hose end to attach to pump#2 on the tank side and then ran the #2 fuel line to the outside of the car to the front; from a capped hole I found which I also filed down and loomed the line and then undercoated the hole to seal it off.

Both pumps are powered by dual fused 8 gauged Rockford Fostgate Power wires coming straight from the battery to (2) Bosch SPST 30 amp relays and both are trigged by the stock fuel pump feed wire. Stock pump #1 is grounded by the oem ground, and Pump#2 is grounded to the hat. Both relays are grounded under the seat with 8 guage also and gold ring terminals.

My install is very clean and I tested everything and both pumps are functional and flowing just like the supra did when I done its dual pump setup.

Dx3

iTrader: (13)

Are you guys having any problems with increased vapor in the cabin? Mine is pretty bad and I run duals. I have no leaks anywhere, but don't know whether I should replace the gasket on the tank (where the 8 screws are) or else just epoxy around it...

Thoughts?

Jonny

motorheaddown

I get vapors, too; and I think it's from the steel-braided fuel line. Next time I'm working on the tank access, I'll probably try a teflon line. Hopefully, it won't seep fumes.

Going through the bottom of the tank is probably the best solution.

-scott

Supra Dr

iTrader: (14)

So it's the braid lines that make them stink in a garage. Always wondered
about that. Every modded fuel car I've seen does that. Doesn't your
trunk wreak w/ fuel since the line comes out the top?

VNT, Haha yah... I set everything up for 1000hp in case I feel the
need & don't have to back track.

tuninghaus

iTrader: (2)

anyone ever try running an external pump from the stock fuel tank? i'm not even sure if it's possible to drill the back/bottom of the stock fuel tank to run an aftermarket external fuel pumP

i used to use walbros and from experience they aren't the most reliable pumps!

Supra Dr

iTrader: (14)

Yep thats what I did.

vntperform

iTrader: (15)

I had this problem also but just recently remedied it, no more fumes. I can fill you in on the details if you want? And I didn't opt for the Mvp $475 fuel hanger.

vntperform

iTrader: (15)

I tried epoxy and still had the fumes. So I contacted Eric, the guy who helped design and build the TTC Hanger that mvp sells. I couldn't see myself spending $475 for the hanger. So Eric showed me the light by helping me get the fitting that I could feed the +POS wire through to avoid the fumes and I got it and installed it and I aswell forgot to put a o-ring on the bulk head fitting that is on the hat and now all is well. No more fumes and I avoided spending $475 on a hanger. Woohoo!

tuninghaus

iTrader: (2)

drilled a hole in the bottom/back of stock tank and used an external pump?
any pictures???

Supra Dr

iTrader: (14)

Sorry feeling lazy pics here:
https://www.clublexus.com/gallery/sh...0&ppuser=13123