LS swap dual tank harness kits!

[gmachinz]

If anybody is interested, I literally just finished a 3-gang relay kit that replaces ALL of your existing dual tank wiring so that you can run (for example) 2 1987 TBI sending units and run 2 Walbro 255 fuel pumps. I'll be listing these shortly in the FS section with pics! Prices are $319.99 for these harnesses and include a NEW 65 psi GM style selector valve!

[gmachinz]

Here is the basic harness layout for it-there is a main IGN control relay and (2) fuel pump relays-a LH and RH. The control relay activates the selector switch and the pumps as well as the GM style 6-port selector valve-which btw is NOT your standard NOS GM valve or parts store replacement-the one I include is rated to 65 psi.

[gmachinz]

Closeup of part of the harness-this one has leads to plug directly into the pigtails from the Walbro style replacement fuel pumps when using an 87 style sending unit.

[656mx]

Do you sell it without the valve? I already bought and installed one for higher pressure. I was going to build my own harness but this would be a big time saver. It's for a ls swap 86 short bed.

[gmachinz]

Yes I can! Without the valve cost is $65 less on either kit!

[656mx]

You have more than one kit? Have a link or something? I'd like to see what you have.

[foamypirate]

These look really nice, as always! I'll need to save some buckaroos, but I'd definitely be interested. I don't like the idea of my current factory setup where the Walbros are drawing all of their current through the 28 year old factory wiring and the selector switch.

[ElGracho]

These valves are rated to 65 psi and are plug and play to the 1987 GM fuel selector valves. If you buy one from AC Delco it will be marked Pollak just like the originals were. Many people have used these with the corvette fuel pressure regulator (58 psi) for LS/Late Vortec applications.

http://products.pollakaftermarket.co...n-valve/42-159

[gmachinz]

It uses a factory style switch but must be on/off not momentary. As long as it does not say depress fully you're good. I thought I listed the AC Delco/GM part number for it....if not I can look it up-it's still in dealers for about $8-9.

[hatzie]

Originally Posted by gmachinz

It uses a factory style switch but must be on/off not momentary. As long as it does not say depress fully you're good. I thought I listed the AC Delco/GM part number for it....if not I can look it up-it's still in dealers for about $8-9.

Ask the counter goon for a 1987 GMC K20 "TBI" fuel tank switch.

The AC Delco part number is in post #2 the Dual Tank Theory of Operation thread. Here--->http://67-72chevytrucks.com/vboard/s....php?p=8152326

[Popeye75356]

Gmachinz,
I'm struggling a little and thought maybe you could lend some insight. I've taken the path of dual tanks on my 84' 5.3 swap with the following:
1. Walbro 255's in the tank
2. 87' tanks
3. 87' sending units
4. Pollak 42-159 6 port selector valve
Now I'm a little confused about how I'm going to power my in-tank pumps and also my OEM switch says "depress fully"????? Clearly I'm a green hat as this is the first time I've ever attempted a frame off so any help or suggestions would be greatly appreciated.

Thanks
Popeye

[gmachinz]

You need to use a 1987 fuel tank switch-the TBI trucks didnt use the depress fully switches-those were momentary and powered a shuttle valve inside the selector to open/close LH or RH fuel tanks ports.

[Popeye75356]

gmachinz,
Do you know of any vendor that I can source an 87' harness and switch from?

Popeye

[Popeye75356]

gmachinz,
Will your harness work as a "plug and play" solution with the 87' sending unit wiring ? If so do you have any available ? Looking to avoid the need to fabricate wiring based on this diagram that a Painless engineer drew for me today.

Popeye

[gmachinz]

If you only need a harness w/o valve I’ve got them available! I’ll PM ya!

[Mattchu60]

Anyone know if the stock lines will be fine at 60 psi? I think its gonna be ok - aftermarket hose appears to be rated at 100 psi or so.

[RADustin]

you should replace the rubber lines when doing the swap. Also make sure the steel to rubber transition has some sort of hose barb. Sometimes I mildly fare the metal tube to bite the rubber.

Cheap insurance to avoid a fire or worse.

[70inbville]

do you make this harness that will connect to stock gm in tank pumps rather than the walbro pumps?

[bh86]

This is awesome!

[TonyC77]

Originally Posted by gmachinz

If anybody is interested, I literally just finished a 3-gang relay kit that replaces ALL of your existing dual tank wiring so that you can run (for example) 2 1987 TBI sending units and run 2 Walbro 255 fuel pumps. I'll be listing these shortly in the FS section with pics! Prices are $319.99 for these harnesses and include a NEW 65 psi GM style selector valve!

How can I purchase this kit?

[gmachinz]

PM sent!

[85Misac10]

Originally Posted by TonyC77

How can I purchase this kit?

You will be happy with this harness, i recently purchased one and wow the quality of it is better that oem.

[85Misac10]

Originally Posted by TonyC77

How can I purchase this kit?

You will be happy with this harness, i recently purchased one and wow the quality of it is better that oem.

[gmachinz]

Originally Posted by 85Misac10

You will be happy with this harness, i recently purchased one and wow the quality of it is better that oem.

Thank you for your order and honest evaluation! I simply build them exactly as I would use them myself.

[lts70]

Installing a FITECH TBI in my friends 1973 SWB 4X4 454. We have installed saddle tanks and sending units from a 1987. We also have selector valve and switch to fit the same 87. And Delhi pumps form a mid 90s truck. Will your wiring harness work well with this set up?