ok so the side hole is for boost signal so what is the top one for???

 

You hook the boost controller to the top port. You should hook up the boost control solenoid so that it will vent air from the top port when the solenoid is off, and feed it boost pressure when the solenoid is on. That way, the solenoid regulates the pressure to the top port, which controls how much boost you get. The side port on the wastegate should always get full manifold pressure. With the top port disconnected, you will get boost in line with your wastegate's spring pressure.

-Max

 

And make sure the side port vacuum line stays on nice and tight!! If it comes off the wastegate never opens.

Not that I have done this or anything... Heh heh

 

Like Max said, full manifold pressure.
So, it needs to source pressure between the throttle body and the compressor side of the turbo.

J