I've just bought a gt but there is a problem with the boost it has a tongs gt spec turbo and a 38mm tial external wastegate which I've been told has a 1bar spring in it, but is only boosting to 0.5? When you take the vacuum pipe between the wastegate and turbo off it boosts too much then and the boosts keeps cutting out? Could it be a boost leak somewhere or would it work if there was some sort of bleed valve in the vacuum pipe? All help is much appreciated!