Gen 3 ECM options

[Steve1982]

I work at a yard full of 00 to 05 gm truck platforms. I have a 6.0, 317 heads im going to use BT stage 2 turbo cam, no boost yet. I want to find the best computer out of these trucks I see them just thrown away every day, I pull all the wire out of the cars so I know. I'm putting this in a 91 OBS, all stock 4L80e i use this truck for everything, pulling in the mountains is where it lacks now. Just cheaper to do an LS swap then try and make the same power out of the stock bbc.

[2xLS1]

There are basically 2 types of Gen 3 PCMs. 99-02 blue/red connector and 03-07 classic blue/green connector. You can flash any 99-02 calibration in any blue/red PCM and any 03-07 Classic calibration in any blue/green PCM. You should decide if you are going to use cable or DBW throttle body. If cable, match a 99-02 6.0L 4L80 wire harness with any blue/red PCM. If DBW then match a 03-07 Classic 6.0L 4L80 harness with any blue/green PCM and grab the pedal, TAC, and throttle body and make note of the year those parts came out of. I would avoid 06-07 Classic and stick with 03-05. Get those all out of the same vehicle. And since you have access to a lot of trucks, try and find a 02+ 5.3L with VIN Z (8th digit in VIN) and get a set of those injectors. They will be Flex Fuel and bigger than what the 6.0L has. Grab a set of E fans and the fan harness from any 05-07 Classic with a 4.8 or 5.3. The fan harness is bundled in with the headlight harness. You can decide what year/calibration is best to start with after you have sourced all the parts for the swap.

[Steve1982]

Thank you about the injectors, I forgot to put in the post I have a set out of a 09 express van that had a 6.0 and flex. I know I wanted that engine but customers paid more than I had at the time. I have found two ecm's with both cable and dbw, I know this because I pulled them out of a dbw, but the circuit board has the provision for the iac. I was hoping to find the holey grail ecm. And wiring I can get what ever one I need.