JonQdiesel

First post here, have been searching but really do not know what I will be needing to create my own harness. I am swapping a LM7-Turbo / T56 build to my 1966 chevelle. I am in the process of getting my turbo build going and about to build mounts for my motor. Not too familiar with EFI. I had purchased a JY takeout LM7 donor. It has all the connectors but no ecu / pcm harness is cut. I am researching megasquirt kits which I think I may go this route. But is the megasquirt acting as the new ECU / PCM units. What the hell do I need to get to control this engine. I would like the ability to control / tune the engine. I would rather not deal with sending stuff out to flash the ecu/pcm for new tunes. I would like to do this on my own. Main questions are really what is needed when starting with just the connectors on my engine.

bfurches

iTrader: (12)

For a first question.....it's a loaded one....but I will try to help as much as I can.

First off, I personally would recommend staying with a OEM PCM and Harness. The factory stuff has proven itself extremely capable time and time again, and I for one don't see the need to reinvent the wheel.

As for sending things out to be "flashed"....I would stay away from that whole concept entirely. I don't believe in mail-order tunes...but again, this is just my opinion. If you are new to fuel injection (in the sense of a custom conversion), spend some time on EFILive or HPTuners forums, and get familiar with the terminology and science behind the systems. There are a lot of very smart people on those boards (here as well) willing to help as long as you do some homework and ask the right questions. Once you have acquainted yourself with the available options, you can purchase one of the tuning solutions and have the ability to make adjustments on your schedule, not the post-offices.

Moving on to your harness....I strongly suggest you start with a complete un-cut unit. First off, stripping the loom and tape off a stock harness and tracing the wires from the PCM connector to the end source plugs will help you to understand the routing of the system and how things work (this is invaluable when you start out). Also, it is much easier to delete the connectors and pins you don't need, versus tracking down the ones you need to re-install.

If you get in a bind and you can't find a complete harness locally, get in touch. I have a few cores I could sell you (I also have some PCMs).

If you take your time and study the schematics, braking each segment down....the task at hand is really not that bad. It just takes some patience.

Hope this helps.

JonQdiesel

Yes, thanks for the reply. As for ecu / pcm. I think I am familiar with the idea of taking the stock harness and basically connecting what i need to make it work. My question of ECU / PCM which whould be the ones that I order. One for my specific model year engine or any ls based ecu / pcm will work as long as its for the t56? I believe this is probably where I am getting lost. What do your cores run roughly if you want you can pm me price. I have seen on ebay and they seem to be a bit high for just a harness?

Again thanks in advance for the reply.