Hi All

New to turbos and boost and had a couple of questions. On Idle the boost gauge is showing as -10/-15 on vacuum, whilst the car is stationary on revving the engine fairly hard the boost gauge moves up to 0 and no more. Is this because revving the car when stationary won't show boost as the car is not under any load? I thought the car would still show boost even if revving whilst stationary. The car should be making 18psi.

Thanks in advance for your answers.