my mate tried to turn the boost down on his saf but no matter how much you loosen the actuator off it still boosts 24psi then drops down to 14. any help would be great as he's had enough of it and reckons he gonna sell it

 

when he bought the car it was stage 1, then he bought stage 3 kit and decided he prefered how it drove on stage 1 so this is why he needs to turn the boost down. he has put 2bar map back on along with the stg1 chip. he has tried changing the actuator, leads, plugs, turbo, basically everything as he has another lot of running gear for his mk2 sitting in the garage but nothing seems to make any difference