Thanks mate makes sense now.

Only other thing was when i turned it the nut came loose. Is it supposed to do that ? Does getting back in the car and driving / boosting again tighten it up ? Thats kinda what got me confused. Is there any advise or technique for how to get the optimum setting > ie. enough good boost but not to much which as you said is bad for the engine ?

It is a stage 1 car.