Yes it will run on the stock ecu. The stock ecu has a fuel cut at a particular pressure this will not be able to bypass. 1.1 bar? Can't remember exactly. You can use the controller to get just under the cut though.
You are saying literally all the wires are black? That would make it hard to figure out. There should be 1, 2 or 3 groupings of wire. The grouping of wire with 4 wires in it is the important one. It should have black, red, and two other colors.
- The Black is earth, find a nice nearby bolt that goes through metal and run the black under that (with a ring terminal or something)
- The Red is switched power, you need to find a power wire that only comes when the key is on. I have used the switched power wire for the stereo, with a vampire clip.
- the other two wires in that bundle of 4, go to the boost solenoid. They are not polarity specific, so you can pick which goes to what.
- the vacuum line on the back of the Blitz needs to be extended and connected to a vacuum source on the intake manifold with a "vacuum tee."
- The boost solenoid also needs both it's vacuum ports connected to the turbo's vacuum hose lines.
If there are other groups of wire, they are not used. If all the wires on the back are black, I recommend dumping this and getting a more modern unit. I used to have the GFB EBCS, it worked great.