The ST165 and ST185 did not come equipped with an air bypass valve for turbo protection.  Due to the lack of spacing and customer support kits were never created for these vehicles.  Here is the information about the universal valves available so that you may create your own system.  If you are buying a Blow Off Valve, regardless of brand, be sure to get the universal kit unless otherwise specified.  For more information about what a Bypass Valve or Blow Off Valve is, visit the BOV FAQ.  Click for listings:

Bypass Valve                           Blow Off Valve