Ls Swap Checklist

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Turbo4whl

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Location
Downingtown, PA
First Name
Wayne
Truck Year
1974
Truck Model
Jimmy
Engine Size
350
LS Swap gurus, ......

Things I'm still unsure of:
1. I can use my existing fuel tanks/sending units, I'll just need to source a frame mounted fuel pump/regulator and figure out how to plumb a return (will this require tbi sending units for the tanks?)
I am not the LS swap guru, but I do have to trucks with LS engines.

About the frame mounted pumps, electric fuel pumps need to be close to the tank and low. Heat is the big enemy of an electric pump. Heat shield is a must to protect from exhaust heat.

@Bruce Wingate idea of a pump in the tank you already have sounds like a much better plan. Reading about many LS swaps on this forum, it seems most everyone swaps to a later tank and installs the correct pump.
 

Slooptin

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Location
Denver
First Name
Vance
Truck Year
1985
Truck Model
k30
Engine Size
454
I'm planning on a very similar swap, except I'll have a 4l60e instead of the 4l80.

What are you planning for fuel? I would like to keep my dual tank set up, so I think i need to change the switch and the fuel selector valve from an '87. My tanks are brand new so I might go with the holley in-tank pump with the bigger mat that doesn't need baffling (almost the same cost in the end). I might also just run with one tank for a while
Still haven't quite figured it out. I ended up putting the engine on a stand for the time being because I want to swap camshafts before the engine goes in the truck. plus this gives me an excuse to meticulously go through the wiring harness and label everything.

I think I'll end up going with a walbro pump and tbi sending units, but I've also made a post about adding a suburban dank to run with the dual saddle tanks to have 60+ gallons of fuel on board which would help with long road trips. I'll try and post about how i set up the full fuel system when I'm done
 

Camar068

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Kentucky
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David
Truck Year
1986
Truck Model
K10/LM7 5.3/4L60e/np208/3.73/32"
Engine Size
10 yrs Air Force
Still haven't quite figured it out. I ended up putting the engine on a stand for the time being because I want to swap camshafts before the engine goes in the truck. plus this gives me an excuse to meticulously go through the wiring harness and label everything.

I think I'll end up going with a walbro pump and tbi sending units, but I've also made a post about adding a suburban dank to run with the dual saddle tanks to have 60+ gallons of fuel on board which would help with long road trips. I'll try and post about how i set up the full fuel system when I'm done
guessing you'll need to fill the dual tanks (as needed) with the 'burb" tank or you'll have to find a 3 way switch/valves etc.
 

Hunter79764

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Sep 1, 2021
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Location
Grand Prairie, TX
First Name
Shawn
Truck Year
1987
Truck Model
Suburban V20
Engine Size
350
May be too late, but for future reference, generally there's no problem getting a separate harness to work, especially if you plan on getting a modified harness done from any of the major players out there. There's a couple of fuel injector plug options, a couple of O2 plugs, and then Gen3 vs Gen 4 differences, but usually none of those are a big deal and can easily be addressed by your harness provider. I have heard (but can't confirm) that Van ECU's are a pain to deal with, so avoid if possible.
 

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