eilax53

iTrader: (2)

Hey guys,

Not sure where this thread belongs but if a mod wants to move it to the right spot go for it

I am currently doing a 5.3 Truck engine swap with the LS1 intake into my 84 corvette and am having trouble with the type of engine harness and ECM to get. I am electrically inclined to do the splicing and to figure out where wires need to go and all of that stuff but I am not sure which harness to get. Should I get a truck harness and splice in the pigtails for the injectors and what ever else needs to get spliced in or should I get an LS1 harness from a camaro/firebird or get a Corvette LS1 harness and modify it so its set up for a cabled throttle body?

And ECM. I need one to get flashed, correct? And I also heard I have to turn off some of the stuff on the ECM. What stuff do I need to turn off and how?

Also I heard that some years are weird, like the 98 camaros. Why is that?

Any help will be greatly appreciated
Thanks
Cory

spartanv8

iTrader: (4)

Well don't quote me, but as I understand it, you can use either harness, truck or car, and either pcm, truck or car, just match the two. Truck harness, truck pcm. I'm planning on doing the truck harness with my 5.3, with truck pcm, and hacking up the injector plugs to fit ls1 injectors and intake.

Somebody that does the reflashing for the pcm could tell you more, but pretty sure most people get rid of VATS, 2nd O2 sensors, emissions, etc.. As I understand it, you just leave the DBW alone, just don't connect it to anything and it will be fine with the cable TB.

Anyone care to elaborate or set me straight?

gofastwclass

iTrader: (2)

I was told the drive by wire PCM's aren't compatible without all the DBW stuff unless that programming is removed from the PCM. I also read something to that effect in the Street and Performance catalog.

Something else to remember is the 24x vs. 52x wheel on the crank / cam. You need a PCM that is compatible with whatever you have on the engine or it won't run. If memory serves me correctly the 52x didn't come into play until 2004 - 05 but I don't have my notes in front of me (I'm at work).

garys 68

iTrader: (1)

I did a truck 6.0, LQ9 with an LS1 intake on my 68 vette. Get the original harness and computer for the truck. It will work everything correctly, ie DBW, crank/cam sensor, etc. When you send your computer out for reprogramming, just tell the programmer which injectors (LS1 or aftermarket) you'll be using. Buy a set of LS1 injector pigtails and you're set.

spartanv8

iTrader: (4)

When I bought my motor, it was supposed to come from the yard with a harness, but they forgot it. Now I'm trying to get them to send it (truck harness), but the lady keeps telling me that the connector that I want, which hooks to the pcm, just goes to the fuseblock, and asks me is that what I want? I tell her I need the engine harness, which goes between all the sensors and injectors, and the pcm.
Do I need both of these harnesses then? There are two plugs on the pcm, I had just assumed that they both went to the engine wiring harness...