no thats not true.

the amal valve is a bleed valve, just an electronic swith one. so by removing it youre decreasing your boost.

the boost limit is on the chip in the ECU, unless you chip the ECU you will not remove the boost limit.

i dont understand why your mate has removed your amal valve. you only want to be doing this if you're replacing it with another bleed valve, as above the standard actuator preload will give you 2-3PSI without a bleed device.

i woudl reccomend you get it taken to someone who know whats theyre doing, as you're not running a standard engine (1900), so you may need to make further adjustments over standard. plus it wont cost much money to get it all set up properly, its not a black art.