Cheers John. They didn't happen to measure the cam duration, overlap or lift did they ? The valves are sodium filled as standard, Dave Crissell told me that when he ported the head. I think the KR cams are fine because the rolling road plots of power and torque are very smooth. The loss of boost may be a leak, also could be the G60 seals (they were replaced no more than 5000 miles ago though, so I doubt it). Not sure how to check for a boost leak really, perhaps some controlled smoke ? I may just be chasing my tail as 6psi might be all that the G60 can muster in this configuration !!