280 LPH Supra fuel pump installed

[Jerryl]

Add some voltage and this pump will kick the Walbro's ARSE!

MKIV.COM - Fuel Pump Upgrade Guide

I just purchased 3 of these since I am never going back to a Walbro.

 

[turbofabricator]

Jay, I agree that you could loose the prime if you have a low fuel level and park on a hill. (facing up) I have not had an issue with that happening, though. Although, I was told by the Chevy salesman that even a new Tahoe has the same problem, too. If I drive the our Tahoe, I keep the fuel tank above 1/4, but my wife on the other hand..........

Ron, I would need a good sending unit. Either a new hanger for a carb'd G-Body, or a good GN one. If I could find a supplier for the electrical connector, I would make everything in-house. (I tried to find a source for a electrical connector that is gas and alcohol compatable, but came up empty handed.)
I would fab up a 5/8" or 3/4" pick-up and weld on a -12AN fitting on the end or provide a barbed fitting if you want to use push-lock hose instead. The pump can be mounted on the fuel tank straps, or I build a bracket that replaces the stock spacer for the tank straps. Mount the pump in rubber/silicone cushions to keep it quiet. Routing a -6/8AN hose up to the front of the car and using a AN fitting on the fuel rail. If you are going to runa BIG external pump, then you will need to run an aftermarket pressure regulator with a larger internal orafice. I have a fitting that will allow you to run a stock fuel rail and run an external regulator and -6AN hose.
http://www.turbobuick.com/forums/general-turbo-buick-tech/240060-revised-regulator-fitting.html

http://www.turbobuick.com/forums/ge...210396-fuel-regulator-bypass-fitting-6-a.html

I am surprised that no vendor has made any of those things. I had to have 25 parts made or the machinist wouldn't do it for me. (so, I still have the pieces left for a few of them)

I could build a modified sending unit and post a pic of it if people want to see what a sender with a 3/4" pick-up tube would look like compared to a stock sender. I would have to order a new sending unit, unless someone has one that they want modified for a reasonable price. (hey, I'm off work right now, so, reasonable means a peanutbutter/jelly sandwich, soda, and my mortgage payment. )

 

[ronbuick]

what fluid is used to test a pump to see what its pumpng capability's are, thanks.

And Ken, I will PM U!

Ron

 

[t-topflyer]

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[ronbuick]

I read somewhere that the current draw of the Denso pump is 16A, I know that that has to be too much for the stock wiring of the sender, the rest could all be relayed using the existing harness, but how does one upgrade the hangar or sender wiring to accomodate the increased amperage??

Ron

 

[Just a Six??]

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[SMS]

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[turbofabricator]

I read somewhere that the current draw of the Denso pump is 16A, I know that that has to be too much for the stock wiring of the sender, the rest could all be relayed using the existing harness, but how does one upgrade the hangar or sender wiring to accomodate the increased amperage??

Ron

GREAT question. The wiring to the sending unit is piece of cake. (hot wire kit) Upgrading the wire to feed the pump through the sending unit is a PAIN!!! I ended up using a nylon 3/8" bolt and nut, and drilling a hole through the center of of it. I tapped the hole 1/2 way through with a 10-32 tap. Then I threaded a stainless allen screw through the bolt with an electrical connector under the head. By only tapping the nylon bolt half way, it allowed me to get the allen screw started straight and then it became a ny-lock arrangement to keep it tight and to seal out fuel passage. Then I placed an O-ring under the head of the nylon bolt and then tightened the matching nylon nut on the bottom side of the sending unit. (I also drilled a 3/8 hole in the top of the sending unit, but you already figured that out, I'm sure.) I did this for both fuel pumps (my dual pump, dual outlet sending unit) I also safety wired the nuts together to prevent them from coming loose. (dang airplane guy thinking too much here. ) This allowed me to run two separate wires to feed the high amps to each pump, which would also allow a staging of the pumps if I needed to. I tried to source out a gas and alcohol resistant bulkhead connector that would carry 30amp for each wire, but was never able to source one. It would have to have 4 min, but best with 5 wires going through it. (one for each pump, two grounds, and sending unit wire. I simplified the wiring by grounding though the hanger assembly inside the tank, and then have a separate ground wire connection on the top. If anyone knows where to source a fuel resistant connector (new) I would love to know about it. The OEM makes them, but I have not found the source. Even Caspers didn't know. I figured he would know if anyone did. For those with ample time to search the web for a fuel connector, PLEASE do. I'll buy you a beer or three. (or maybe a new sending unit. )

 

[87GNSteve]

Update

Yesterday I recieved the sender for a N/A Gbody, I wanted to see if a Supra double pumper was possible.
So today I dropped the tank again and did some R&D.
It looks like a side by side pump set up would NOT be possible.
[See a comparison pics of the pump opening compared to the single Supra/Denso pump.]
The N/A sender is IMO a great candidate for mods. If I was to attempt a double pumper I would have one pump mounted horizontally and the other mounted vertically [See pic of how this would be oriented.] That would be the only way to get the pumps into the tank. The hanger would have to be modified to remove the vapor line and add a 3/8 line in its place. Or add second feed line and leave the vapor line where it is.

The other nice thing about these Spectra N/A hangers is you can easily remove the float arm and attach it after you drop the assembly into the tank, that is how I had to do this install. NO MORE notching the tank!

I read somewhere that the current draw of the Denso pump is 16A, I know that that has to be too much for the stock wiring of the sender, the rest could all be relayed using the existing harness, but how does one upgrade the hangar or sender wiring to accomodate the increased amperage??

Ron

Interesting you asked this....
So since I do not have two Supra pumps (yet, they are on the way) I decided to use the Supra pump attached to the N/A hanger in the horizontal position and upgrade the wiring.
I also used 10 AWG stranded copper wire that I got from Lowes of all places, its gasoline and oil resistant and says so on the jacket its some hard core stuff! The pump goes right in but angleing with all those baffles makes it a challenge I had to shorten the outlet line a 1/2 inch so the pump wouldnt stickout as far.
The N/A pump sender only has a single wire socket (for the gas gauge) so I drilled that out to 3/8 and used a plastic bushing to protect the wires.
I ran 10 gauge wire to the POS & NEG terminals fed them through the small hole I had to extended the gas gauge wire using some 14 gauge wire; I fed that through the hole too. There wasnt much room left so I put some epoxy and sealed the area up. [See pic.]
The N/A hanger has a ground wire attached with a ring terminal this must be used or the Fuel gauge will not work; I made a new ground connection for the hanger gas gauge by just sandwiching it betweent the tank strap/ bolt.
I ran the pump's POS wire directly to the 10 gauge wire on the hotwire relay and the pump's 10 gauge ground to the body where I had an exsisting ground already.
Took the car for a test drive flogged it a bit and it roars like a Lion.

I AM MISSING PICS OF THE DOUBLE PUMPER MOCK-UP, I WILL POST THEM TOMORROW

 

[TurboMonte 2]

The Walbro 340 flows 255 lph on a good day with proper voltage.

That 255 lph rating would likely be w/ 13.5V "at the pump" and at 43#psig discharge pressure...just like the Denso "280 lph" would be rated...

 

[87GNSteve]

Here is a pic of how I think the Supra pumps can be mounted in order to have a double pump system.

 

[KWIKR 1]

Here is a pic of how I think the Supra pumps can be mounted in order to have a double pump system.

Nice thinking !!!! next question.....will it fit into the tank ???? makes me wonder if you welded/silver soldered a AN fitting on the end of that line , why you couldn't get two Bosch 040 or 044 pumps on that hanger .

 

[ronbuick]

87gta, why could you not use 1 denso and 1 walbro as the 2nd pump, a known good quality or maybe a older walbro to kick on at a cetain boost level, cause it is smaller and might just give you the xtra room needed if you do need it, I do not know for sure, now I beleive the 10G wire is to heavy for just 1 pump and not needed, 12G should be enough, but if using it for 2 pumps it might be needed, at this point I'm not really sure of the current draw
of the denso pump other than what I read somewhere and this needs to be verified. Good work BTW, also what is that part# for the n/a sending unit or the application, thanks.

Ron

 

[87GNSteve]

87gta, why could you not use 1 denso and 1 walbro as the 2nd pump, a known good quality or maybe a older walbro to kick on at a cetain boost level, cause it is smaller and might just give you the xtra room needed if you do need it,

I thought of this also it would certainly save on cost.
What I am not sure of is; if you have one pump that is much more powerful than the other and they are tee'd into the same line will the stronger one back feed into the outlet of the weaker pump?
I mean we all know if you have 40 psi and 65 psi it DOES NOT equal 105 psi
So I have been kicking this around in my head the last few days. Not really sure what happens under those conditions..
I do know that the Supra pump will go into the tank in the horizontal position now with a second pump added it looks like a posibility. I'm gonna need to install my tank w/ velcro soon with all this in and out

I do not know for sure, now I beleive the 10G wire is to heavy for just 1 pump and not needed, 12G should be enough, but if using it for 2 pumps it might be needed, at this point I'm not really sure of the current draw
of the denso pump other than what I read somewhere and this needs to be verified.

Well on Caspers hot wire pump which I have the line from the Alt is 10G and then drops to 14G or 16G (tiny) at the factory connections I believe 10g Is the most you would want to go. and I did notice a drop im my BLMs after the new wiring-- I need to lean it a bit.

Good work BTW, also what is that part# for the n/a sending unit or the application, thanks.

Ron

Rock Auto sells the N/A sending units for 41.89 I printed the computer screen and went to the local Advance and they price matched and had it next day.
The Spectra premium P/N s are
FG08A N/A sender w/ 3 outlets
BTW the SFI hanger is FG156A and still made.
There is a FG08B N/A and that only has two outlets.


Other thoughts...My car is not at the level where I need two pumps (yet) So, ultimately I will go back to the single vertical mounting since this allows the pick up to sit lower into the tank (like stock) than the horizontal mounting. and If I needed to upgrade I know it can be done.
But for any one doing this the horizontal pump should be the secondary/booster unit and the vertical the primary this is because of the fuel level in relation to the fuel sock the secondary pump should be fine as long as there is 1/4 tank or more. I will do some more real world testing in respects to this to see how far low it will go. ( I know its best to keep the level at least 1/2 high. but what in case of a hurricane evacuation I need to get in my GN and go!:biggrin:

 

[GNVYUS 1]

Since Walbro's are dying within 20 miles on cars there is not point in running one at all until they figure out what's going on. The Walbro as the second pump would be a huge No No IMO as you'd only find out it's dead while WOT.

Running twin Denso's is beyond twin Walbro's so you'd have a fuel system for low 9's right there.

The 044 is a bigger pump than the Denso and I doubt you can get it to fit horizontally in the fuel tank with the bowls so close all around the pump. The 044 barely fits as is with the sock on it so it would be tough for two but maybe in a NA tank?

I like the NA sender idea, just redo the wiring and tube end fittings and you'll have a nice upgrade.

Let us know how the fuel gauge display is after the install.

 

[87GNSteve]

Nice thinking !!!! next question.....will it fit into the tank ???? makes me wonder if you welded/silver soldered a AN fitting on the end of that line , why you couldn't get two Bosch 040 or 044 pumps on that hanger .

Why not try?
The sender is cheap enough where you could experiment; and its great that the float arm comes off and installs easily through the tank access.
Stay tuned I have another Supra pump on the way so we will see if they fit.
Bosch or Denso either has to be better than the Walbrokes and parts store junk.

 

[Chuck Leeper]

My injector..

what fluid is used to test a pump to see what its pumpng capability's are, thanks.

And Ken, I will PM U!

Ron

bench uses the aftermkt equivient of stoddard solvent.
[Mineral spirits will work.]
They have a sp gr of about .74.. right close to gas sp gr.

 

[kingots2004]

anybody know how much bigger a 040/044 bosch is compaired to the supra pump?

 

[TurboMonte 2]

While I think Richard Clark will be testing one of these Toyota "Twin-Turbo pumps soon--I went ahead and ordered a G77-FPA "Kit" from Racetronix--including their "machined inlet" Walbro GSS340 to make it a 340M. These have not had the massive failures as with Walbro's own F...169 replacement for the 340...

 

[t-topflyer]

While I think Richard Clark will be testing one of these Toyota "Twin-Turbo pumps soon--I went ahead and ordered a G77-FPA "Kit" from Racetronix--including their "machined inlet" Walbro GSS340 to make it a 340M. These have not had the massive failures as with Walbro's own F...169 replacement for the 340...

I installed my Racetronix 77-FPA kit today eventhough my Autozone E3270 was still going strong. Completely different installation and pump than the last 3 (F...in...169s). All different wiring with this kit, and an extra in-tank ground. Hope this does the trick. I'm so good at switching these things out by now that I'm just gonna keep the 3270 with me just in case and put together a roadside kit for pump replacement in case it does.....Hey...maybe I can market an emergency roadside 1-man turbo regal fuel pump replacement kit....