xxbrew1690xx

I have an 1986 Z-28 with a 350tpi and 700r4 trans, I am planning on doing the lq9 swap and the main thing is the wiring, I am kind of a NOOB when it comes to this but do they make harness's plug and play or do you have to make your own? or anyone on here make them? any feedback will be greatly appreciated.

vetteoz

iTrader: (13)

Try the LSX swap Dept

https://www.thirdgen.org/forums/ltx-lsx/

five7kid

iTrader: (14)

I moved it to that subforum.

You know, guys, when you see a thread in the wrong forum, it doesn't do a bit of good to reply "Try the (xxx) forum." If you report it, we'll see it sooner and can handle it.

Anyway, there is a sticky in the top section of the forum about LS1 swaps. There are sufficient instructions and further links to provide all of the necessary details. Personally, I can't see paying someone to do this if you have the LQ9 harness. I'm no wiring wiz, but I've managed two swaps so far, and the 3rd one, which is the most complicated one I've tackled, LQ4 in a '57 Bel Air, still isn't that bad. It's just a matter of paying attention to detail.

Gregs_GSXR

a lot of great info and pics on here, the search in the sub forums helped me a lot instead of search all of TGO.

86White_T/A305

For what its worth dont be scared of the wiring to do the swap.if you have a complete ls1 harness and ecu..its very stand alone.Almost every plug for the engine/trans only plug into their respective sensor from my memory so you cant mix anything up.Mount the motor and trans up,figure out how you want to plumb your fuel system.You dont need to go in depth with depinning the ls1 harness etc unless you really want to reroute how the wires lay out over the motor for a cleaner install.Depending where you decide to mount the ecm you can simply run these wires to the ecm and will run.

12v constant battery power.
12v ignition hot during crank.
Ground
Vss/speedo directly from the cluster to ecm
Tach directly from cluster to ecm
Oil pressure from cluster to ecm
Coolant temp from cluster directly to temp sensor(use 98 ls1 3 wire sensor)
Fuel pump relay trigger wire to ecm
Fan relay trigger wires depending if you have single or dual electric fans.

Being auto I think you need to wire up the brake switch for tcc lockup and park/neutral.
This will get you running..driving with factory gauges working...with the proper tune for vats delete,speedo calibrated and tach calibrated.Everything else will depend on if you retain a/c..cruise control which you will need to research more on.I dont have them to speak on for advice.I didnt have any emissions equipment on my car so any plugs that were not used were simply cut out of my harness.Thats was the extent of wiring for the swap.

It seems super overwhelming when you tear it all down.Its really not..take your sweet time.If the motor is on a engine stand..do what I did..plug everything in,label it.Get the pinout for the ecm(in the ls1 swap sticky thread) everything is numbered which makes it easy to trace wires at the ecm.I tied all all the main ecm power wires together and ran a a main power wire fused to the battery.Did the same for all the ignition wires fused and ran it directly at the key.Made my own fuel pump hot wire relay kit and used the ecm fuel pump trigger wire and started right up for testing.Then I just focused on making it neat inside the car/under the hood.