Just had my manifold and turbo replaced for vxr unit as old one was cracked well I thought it was til I found out it was one of the bolts had snapped off. Anyway I wanted a vxr unit as going to stage 3 so not that fussed, my question is this, before they changed it over my dump valve was quite loud, I was running both new and oe at same time, when they put the new vxr unit on it seemed to go quiet. It is a baileys dv26 I think, are they adjustable? If they are how do you set them? I know it is wrong as when turbo is spooling up I can hear boost leaking out, this happened on my old turbo but not as much.