i cant really understand what you mean about ecu and running map scooby? for talks sake if sti engine fits straight in without any plug in prob, both are jap, and you put sti ecu belonging to engine in and it physically plus in sure that is the ecu for that engine,so it will run no prob, ecu doesnt know but its back in donar car.. when i done Turbo tonys car, that was a 00 irish turbo, and i fitted a ful 00 sti engine in, straight plug in, and started it and run it with stanadrd irish ecu from the irish car, now as i told him he wouldnt be getting benefit of sti engine till he mapped it, but if i had of had an sti 6 ecu and his car was jap aswel i could of used that, could of used it in his irish one but have to change cam and crank terminals around, jap and irish are different.