Oh god.. this is why i never used to belive or buy stuff from the shops were i live.
Previous owner bought the turbos just because he did not want to buy an aftermarket ecu atm. From what i know, they told him that the turbos were interchangeble, it was just a newer model.
And the ecu......... the guy who sold me this one ownes a tuning shop so i thought that he would have some knowledge about this. My previous experience with other car builds told me to double check the circuit board which i did luckily enough. I dont know if a change of o2 sensors and re-pin of cirxuit board is a good idea when you got a new built engine... maybe should consider a aftermarket ecu