As a rule of thumb how much vac is how much boost so your reading of 0.6bar is what you should have as a positive boost with maybe 0.2bar over boost so at most on that reading I would say you should peak at around 0.8 maybe 1.0bar max but if your saying 1.4bar then either summat is wrong or your car has had some serious **** done to it cus my mates evo runs 1.4bar and he has 808bhp