Can anyone settle this for me? , Recently i bought a new gauge for my car but it reads the boost in bars , after i threw it in the car i took it for a spin and it read 0.5 bar can anyone tell me what this is in Psi i was told 7 but then again my car is suppose to run 10 (standard) from what I have been was made to understand , is my gauge reading accurate or is my information source rusty ?