specific LS swap questions

[encasedmetal]

been reading through everything I can but have some question left that hopefully some of you can answer. I am doing this on my 63' gmc btw. if you can answer only one- please chime in.
1. regarding wiring harnesses- I will be rewiring the entire truck SO is there a company that can make all of that for me or would it be best to use the LS engine harness and 1980 complete harness that I have. (I've never wired a car before but willing to give it a shot). I will be running a/c which my truck didn't originally have plus the gauges etc.
2. I won't be using my in cab gas tank and have decided to do an intank pump setup with a tank mounted under the bed. are there any originally LS powered vehicles I can fit back there or is it best to go with something like a boyd's etc?
3. when using LT designed for an LS swap in our trucks- are there any midpipes that fit as well?
4. I am really wanting to run Dakota Digital gauges with the accompanying OBD port- is there anything to know about using these or that I should consider when wiring the truck?
5. if using a t56 trans- what do I need to do to run the slave cylinder with my brake booster or do I need another type of brake booster to run that?
6. If anyone doing this swap has used a donor vehicle to do it and not just bought the engine/trans off craigslist etc- what would you recommend grabbing off of said vehicle (ie what would you not leave behind).

sorry for the long read- and thanks for the future help- hopefully it help others as well.

[Matt Cramer]

Factory LS harnesses aren't the most swap friendly as they're intended to tie in to a lot of things not on the truck. There's a number of places out there that make engine-only harnesses with just a few points to tie into a factory harness.

I'm afraid I don't have much to contribute to the other questions, sorry.

[encasedmetal]

Originally Posted by Matt Cramer

Factory LS harnesses aren't the most swap friendly as they're intended to tie in to a lot of things not on the truck. There's a number of places out there that make engine-only harnesses with just a few points to tie into a factory harness.

I'm afraid I don't have much to contribute to the other questions, sorry.

so you're saying to get a factory harness and run it with a modified ls engine harness. that doesn't help me with a/c, fuel pump, sender etc, gauges does it?

[BR3W CITY]

Originally Posted by encasedmetal

1. regarding wiring harnesses- I will be rewiring the entire truck SO is there a company that can make all of that for me or would it be best to use the LS engine harness and 1980 complete harness that I have. (I've never wired a car before but willing to give it a shot). I will be running a/c which my truck didn't originally have plus the gauges etc.

There aren't a ton of places where the "Body" wiring and the Ls's engine harness would meet, so your best off just getting an engine harness made for you. If your planning on ground-up rewiring the whole truck (We did), the 80 harness won't help you. Between the crappy plastic plugs, all the wires you'll end up moving or removing, its easier to start clean...especially since that will give you a chance to run your A/c controls and any other 12v electronics in the body harness, instead of coming back and adding it all on top.


2. I won't be using my in cab gas tank and have decided to do an intank pump setup with a tank mounted under the bed. are there any originally LS powered vehicles I can fit back there or is it best to go with something like a boyd's etc?

Some folks use a blazer tank back between the rails, and swap its sending unit out or modify the sending unit for a high psi pump. Fuel cells are nice tho.

3. when using LT designed for an LS swap in our trucks- are there any midpipes that fit as well?

considering where most of the headers put the output, the "midpipe" ends up being a straight section. You won't find anything pre-fab to fit, especially without knowing your plans for mufflers, exit, Xpipe, etc.


4. I am really wanting to run Dakota Digital gauges with the accompanying OBD port- is there anything to know about using these or that I should consider when wiring the truck?

There are a few members using this setup, if you take a look through the builds you can see their setups. One drawback to any of the devices that use the OBD port, is that you can't usually piggyback off them. That means that your gauges are unplugged when HP Tuners is plugged in, or when scanning the ecm etc. Not the end of the world, but can be annoying. There are some that have used a OBD port splitter, but I've heard mixed results.

6. If anyone doing this swap has used a donor vehicle to do it and not just bought the engine/trans off craigslist etc- what would you recommend grabbing off of said vehicle (ie what would you not leave behind).

engine, trans, take the wiring even if you don't use it (sell), DBW pedal and tac module, trans cooler, trans tubing/hoses. Steal the Hydroboster if you are using a van or 2500hd, ECM.

answers in italic Franklin Gothic Medium

[encasedmetal]

You sir knocked it out of the park. Thanks so much

[PGSigns]

I am doing a 66 and getting all the swap stuff ready. I put an American Auto wire classic update harness in the truck and it gives me all the power and fuses I will need for all the ad ons like AC, air ride and stereo. I am doing a stand alone engine harness. AAW gives you the option of stock or aftermarket dash.
Jimmy

[BR3W CITY]

Originally Posted by PGSigns

I am doing a 66 and getting all the swap stuff ready. I put an American Auto wire classic update harness in the truck and it gives me all the power and fuses I will need for all the ad ons like AC, air ride and stereo. I am doing a stand alone engine harness. AAW gives you the option of stock or aftermarket dash.
Jimmy

I assume that is a body-side harness?

[PGSigns]

Yes it is a complete harness for the truck. It will allow me to easily install the flaming river column and a Dakoda digital dash. Plus it go rid of all the other wiring problems we have with these old trucks.
Jimmy

[encasedmetal]

Originally Posted by PGSigns

Yes it is a complete harness for the truck. It will allow me to easily install the flaming river column and a Dakoda digital dash. Plus it go rid of all the other wiring problems we have with these old trucks.
Jimmy

*****in. I look forward to checking them out. thanks