Hi!
I am wondering about upgrading my 2003 H2 with a new Vortech 6200 engine with a 6L80E transmission, but I am unshure about the ECM. I know that a new ECM is required, but I am not shure about the compatability between the wiring of the ECM and the rest of the car. Wiring for the engine and transmission I know need a uppgrade, but what about the connection between the ECU and the Car/Speedometer and so on?

Of cource, a Hummmer H2 wiring harness for engine and transmission is going to be used, as the newest models are delivered with the Vortec 6200 engine.

If anyone has any information, I would appreciate it.

PS: Duramax 6.6 upgrade would have been awsome, but due to local regulations, I am not allowed to do so, since the Hummer H2 has never been delivered with this engine.

 

I just finished this swap, I had to buy a 98 5speed ram in the meantime. I can only my afford to keep one of the vehicles, debating which to sell. I just posted a thread with more details on the vehicle

 

Sorry wrong post