Ive seen threads about the 3.4L swaps and Im confused about the wiring harness. Ive always thought that the computers are made specifically for the engines they are used for. I often see different threads about doner cars, yet they are haveing a world of trouble with the wireing. Why cant you just use the computer and stock wireing harness from the doner? Why arent they just plug and go?

Also, With 3.0L and 3.4L swaps, do you have to worry about driveshaft lengths or are 22r, 3.0L, and 3.4L setups all the same length?

 

The harness is to plug the donor ECU into the current harness. If you use the donor harness, you have to remove EVERYTHING. So, rewire everything under the dash, all the idiot lights, the gas gauge, yada yada.

This just makes it plug and play.

I would think tranny and transfer case would have more to do with the driveshaft length than the engine. Not sure on that one though.