Rutager,
A few things:
1.) listen to Jamie- her really understands the nuance of these setups.
2.) Your ITBs probably aren't balanced well enough and that's going to kill anything you do so that should be the priority.
3.) I had som e pulsing noise with my signal initially, then I ran each bank of the ITBs to their own manifold (modified fuel rail) and then each of those to another common manifold and all of the noise went away and yielded a consistent 44kpa at idle.
4.) A large manifold (with 9 ports: 6 for the ITBs, one for the ECU, one for the brake booster and one for the IAC) would be ideal for plumbing an IAC. That was the approach I was going to take until I decided on a hand throttle which has been ridiculously simple to install and operate. It also has the added bonus of being a poor man's cruise control
I sent you an email too