Racing Lower Temp 68C Thermostat For Subaru Impreza Wrx STI Legacy Forester Outback Low Temperature Thermostat opens @ 68 C (155 F) For Forester 1998-2011/ Impreza 1993-2009/Wrx & Sti 1992-2014/Baja 2003-2006/Legacy & Outback 1990-2012 The racing thermostat will significantly lower high engine temperature produced by modified and upgraded turbo applications. Once the engine is fully warmed up the racing thermostat will open up at a lower temperature than standard thermostats, also allowing the coolant to flow through the engine sooner thus reducing and maintaining cooler engine temperatures