r-s-turbo

Basically my car has been sitting 4 a very long time, im guna start a resto thread soon wen i get my arse in gear but n e way ill stop sidetracking........took my rs out 4 the 1st time in ageees and the dump valve now sounds pants and it jus seems realy fcukin slow tbh.

i take it i need a new actuator cuz its not holdin boost?
if so is an actuator easy to fit? i.e. thers like a thread on the stick thing that comes out of it, if i get this the wrong length i take it my car will boost more or less?

does anyone know how much boost you can run safely on standard pistons? could i get the standard pistons machined slightly to slightly lower the compression? or would i just need new ones that are lower comp anyway?