Hello karlos,

At what rpm was the boost surging?
With the electronic boost controller you should be able to tailor the boost curve
vs. RPM.

You should be able to plot your engine airflow demand on the 60 trim compressor map you posted.

Also take a look at this turbo calculator: http://www.squirrelpf.com/turbocalc/index.php

It is quite good.

I input a 1.6 engine, and 250 hp, and .55 bsfc, and 1 psi intercooler boost loss.
I also mapped the 60 trim T3 with these parameters.
It looks like 4000 rpm before you can be at full boost (over 18 psi)

Cheers