The AMS-500 Boost Controller can control 2-Stages and/or levels of boost. The 2-Stages are controlled by Input1 and Input2. Both of these inputs can be configured using a DIP Switch for either Ground or +12 volt activation. Input1 may be configured to function as a “Launch” stage when used in conjunction with Input2. Input2 offers an adjustable ramp rate as well as boost level settings.
Each stage has a range of adjustment from 0 to 40psi with 1psi resolution and is controlled to within .1psi to target using advanced control algorithms. If a setting greater than 40psi is configured the AMS-500 will default to the maximum 40psi allowed. A setting of 0 PSI will turn either stage off.
An optional Safe Mode is available when using a pressure source other than the manifold pressure. The Safe Mode continually checks for the proper pressure increase and will disable the system and open the decrease solenoid in the event of an error condition.
When in Normal Mode of operation the AMS-500 will keep trying to apply pressure to the waste gateuntil its target is reached.
IMPORTANT—The AMS-500 controls the pressure on the Waste Gate so the actual boost level obtained is a combination of the Waste Gate Spring pressure and pressure applied by the controller. (Just like the AMS-1000) This controller comes with everything you need to connect it up and use except for an external air source if desired.
Check out this thorough review from Bimmerforums member "rukman" on the AMS-500:
