I have read many posts, and I think am ready to attempt this swap, but have some basic questions. I have the LT-1 PCM and engine wiring harness, and plan to use those on the new engine, but it appears the PCM can't be located in the original ECM location, the wires are short. Where can I place the PCM? I am using a T56 transmission, and have the reverse lights and speedo hooked up, so I won't need any of the automatic connections. It's a non-ac car so that isn't an issue. I have read about C210,C220,C230, and C100. What does C105 do? The swap should be a good winter project.

 

You can place it wherever it reaches and you can fit it. Mine is a B-body harness and sits on the passenger wheel well near the battery.

As for the different connectors, I honestly only used the C100 and nothing else. All of my wiring goes through the C100 on my car.

 

You need to extend each individual wire about 3 more feet in order to mount it in stock position

 

Is there a clip available to extend the wires? Are the connector ends available, so I could make my own clip? If those two options are not possiable, what is the best way to extend the wires? Splice a wire in between, or take the connector apart, extend the wire, and put the end back on the extended wire?

 

I used an AC delete box and had enough space to mount it in that area....... The harness was from a 95Z28 & I just screwed the LT1 F-Body bracket to the fender well using 2 GM 10mm coarse thread screws with large washer. The LT1 bracket was trimmed a little and the slotted mounting hole slots were made longer for the best fit possible. I also placed a short piece of 3/4" hose under it for a cushion & to set the PCM at a favorable angle ( so it doesn't hit the hood. ) The PCM doesn't hang over the headers where it sits and it's real easy to access.

 

ma I'd hate to give up AC, but I am proly a bit older than you

 

I don't have AC either, so that location would work, however someone told me the heat can negitively affect the PCM. Is this ture? Did you protect it from getting wet, or this that not an issue?

 

you have to de-pin the pcm connectors, and extend each wire one at a time. I guess the only short cut is depending on how you connect the wire extensions. Soldering is probably your best bet but ive seen people use a few butt connectors in their harnesses, but i dont suggest it, if you have one that comes loose its gunna take awhile to trace it. Shoot Pocket a PM, he is most helpful with wiring questions.

 

I didn't do anything to deal with it getting wet in that spot.... Not much of an issue for me because the car is garaged 95% of the time. I am contemplating some type of a cover for it but I want to do some water testing to see if/how/where it might get under the hood first. I'm thinking a thin sheet of rubber over the top & hanging over the sides would be enough if there's water gettin' in. I just DON'T want to sufficate it by wrapping or completely covering it.

Heat WAS something I was worried about. There were a few places on that inner wheel well that the PCM could have been mounted "better". One option that looked promising was to spin the PCM bracket around and screw it into the heater box,.... but all the other options I considered in that area placed the PCM at least partially "over" the headers. The way it is mounted in that pic, It's not sitting over the headers. In the earlier pic I posted you can see how the PCM sits even or just to the left of the blower box resistors; this pic shows that area when the PCM is removed.




I could also make my pass side fan the primary fan so there's as much air flowing over there as possible, But I'd need to find that PCM getting noticeably hot before I would take fan blown air flow from the power steering and Brake side of the Bay.


I'm 41,...... and have removed the AC from each and every one of the 20-25 ars that I've rebuilt. ( Most were T-Top cars, some got all the AC parts reinstalled except for the compressor. ) Hell, My 95 Z has just over 80K and - you guessed it; AC Delete pulley is already installed !

 

IntimidatorZ put his PCM inside of his stock heater box housing. In the place of the condensor.

 

Ah heck, you are in RI, what is considered a hot day there, 75? here in Kansas this summer it was over 112 for a couple of weeks straight. and driving in that kind of heat really saps the Pxxx out of you, never mind being inside a vehicle with motor and road heat. and I am 53, kind of like my creature comforts.