280 LPH Supra fuel pump installed

What wiring are you guys using for this pump?
And
from where are you getting the wires?

Are you using the SFI hanger?
Are you replacing a Walbro?
In the first thread you can see pics where I used the connector lead from the walbro and put two ring terminals on it I do Highly recommend bypassing the small factory wiring and having heavy 10 or 12 ga. wire fed directly from the hotwire it will take some small fabbing but not too much.
When I did the wire upgrade the pump really came alive; that factory 14-16 ga. is too small IMO.
 
Are you using the SFI hanger?
Are you replacing a Walbro?
In the first thread you can see pics where I used the connector lead from the walbro and put two ring terminals on it I do Highly recommend bypassing the small factory wiring and having heavy 10 or 12 ga. wire fed directly from the hotwire it will take some small fabbing but not too much.
When I did the wire upgrade the pump really came alive; that factory 14-16 ga. is too small IMO.

SFI??
I am using a stock GN hanger
Replacing a Walbro 340M.
So the wiring from the hanger to the pump are usable
But from the hanger to the Hot wire kit are not!!
Not a problem.

I’ll go over the thread from the beginning to pick up anything I might have missed.
Thanks for the help
David
 
Got it in Friday and here are a few tips.

Get 14-16 gauge ring terminals for the M5 and M4 Denso terminals.

Use the supplied hose in the Denso kit.

Saw off the part of the float arm that sticks out of the housing. It will not pop out and this will allow you to sneak the pump into the tank without notching it.
The float arm will actually slide towards the pump a tad so you can saw it off in two different positions if you're worried about it being too short.

BTW, Walbro was off 8psi up top and Denso is dead on and was 3psi higher in base pressure.

And my track outing 2 weekends ago on the Walbro took out my headgaskets. :mad: :mad:
 
One cut, float arm nub that sticks out of the housing, you'll see if you try to install it in the tank.

I used 2 stainless clamps to hold the pump to the return pipe and I notched the lower bracket so the Denso would sit on top of that for support. Wasn't that hard at all and can easily be cut with hand clippers.
 
Wiring upgrade diagram

Below is a diagram of how to by-pass the small 14-16 ga wiring that runs to the pump.
Even if a hot wire kit is installed a 24 inch run of that thin wire is there from the hotwire connector to the pump. That just increases electrical resistance and IMO insufficent.
I added 10 ga from the hot wire relay directly to the pump it requires slight mod of the hanger to get the wires in but no big deal. This also adds a heavy ground directly from the pump to the body and leaves the very small factory ground which is needed for the fuel level sender anyway.
 

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How did you seal and insulate the 10ga wires going through the top of the sender? I would build alot of double pumpers, with dual outlets, if I could find an effecient bulkhead fitting that would route 10 or 12 ga wires into the fuel tank. Gasoline is very unforgiving, and I don't want the liability of an electrical short anywhere near the fuel tank. Call me a wuss, but gasoline and sparks make me VERY nervous.:eek:
 
How did you seal and insulate the 10ga wires going through the top of the sender? I would build alot of double pumpers, with dual outlets, if I could find an effecient bulkhead fitting that would route 10 or 12 ga wires into the fuel tank. Gasoline is very unforgiving, and I don't want the liability of an electrical short anywhere near the fuel tank. Call me a wuss, but gasoline and sparks make me VERY nervous.:eek:

:)

Why would you need more than 16Ga wire for a draw of 8 amps over a length of 6"? Do you actually think you can measure a difference in pump performance using 14 or 12Ga?
 
Below is a diagram of how to by-pass the small 14-16 ga wiring that runs to the pump.
Even if a hot wire kit is installed a 24 inch run of that thin wire is there from the hotwire connector to the pump. That just increases electrical resistance and IMO insufficent.
I added 10 ga from the hot wire relay directly to the pump it requires slight mod of the hanger to get the wires in but no big deal. This also adds a heavy ground directly from the pump to the body and leaves the very small factory ground which is needed for the fuel level sender anyway.

Where are your fuses?
 
:)

Why would you need more than 16Ga wire for a draw of 8 amps over a length of 6"? Do you actually think you can measure a difference in pump performance using 14 or 12Ga?

That's kinda what I was thinking...resistance would be minimal at best.
 
Denso 280 pulls 16 amps FWIW and has been run up to 21 volts for additional volume.
 
Denso 280 pulls 16 amps FWIW and has been run up to 21 volts for additional volume.

Yes at upwards of 70PSI.

The weak link in the Buick sender is the factory bulkhead connector and wiring. Our G77 in-tank wiring kit is fine with its redundant grounds etc.

Perhaps our BLT1-BCA we offer to our B-body customers would be of interest to customers looking to use a Denso pump?
 
well i couldnt stand it any longer and ordered the pump a few minutes ago.how much drop would it be if i were to use the factory intank wire also what if i cut the wire up close to the top of the sender and spliced in heavy from there so it would only be like an 1inch of old wire would that make a difference since the bulk head is the actual bad spot in this setup according to racetronix
 
How did you seal and insulate the 10ga wires going through the top of the sender? I would build alot of double pumpers, with dual outlets, if I could find an effecient bulkhead fitting that would route 10 or 12 ga wires into the fuel tank. Gasoline is very unforgiving, and I don't want the liability of an electrical short anywhere near the fuel tank. Call me a wuss, but gasoline and sparks make me VERY nervous.:eek:

On post #49 you can see a picture of the wires coming out of the sender.
Convienently the Denso/Supra pump came with these assorted little bushings and do-dads. I used the white plastic mushroom bushing; I drilled a larger 3/8 hole in the exsisting area, and pressed the bushing in, after running the wires through there was very little room left and I used expoxy like JB weld to seal it up.
 
Yes at upwards of 70PSI.

The weak link in the Buick sender is the factory bulkhead connector and wiring. Our G77 in-tank wiring kit is fine with its redundant grounds etc.

If you set your FP at 43 and run 30 PSI your there (70+ psi FP) already.

Where are your fuses?
Stock location and one off the alt feed in the engine compartment.

Perhaps our BLT1-BCA we offer to our B-body customers would be of interest to customers looking to use a Denso pump?
Send me one I'll see if it works.:D
 
well i couldnt stand it any longer and ordered the pump a few minutes ago.how much drop would it be if i were to use the factory intank wire also what if i cut the wire up close to the top of the sender and spliced in heavy from there so it would only be like an 1 inch of old wire would that make a difference since the bulk head is the actual bad spot in this setup according to racetronix

Thats how I ran it on my original install and it worked.
 
I am in need of a sender unit replacement with horrible low tank level warning, LOL. Yes, I have ran out of gas due to it after I got the car...

What options do I have? I am looking to get one of these Denso pumps to replace my F...in...169 defecto pump.

Thanks in advance...

Mike
 
Wasn't someone on here running the NA sender with the Denso?

Racetronix, post a link for us, I came up with the BLT1-FPA and no BCA.

I get PM's about plug and play Denso kit's as probably does 87GTA so there are people out there who'd buy a plug and play kit from you. And you'd be the only vendor doing it and would be selling the strongest, most reliable single plug and play pump we could buy. Even if it was $250 with the upgraded wiring it's still cheaper than the $$ I spent on headgaskets and the damn Denso.
 
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