Kevin

Alot of you folks are trying to tie in ambient air cooling in relation to cooling the turbocharger down.. As Jerry has mentioned, it is the heat wicking from the turbine housing and radiating into the bearing housing. With the CIS system the idle circuit produces enough raw fuel to cool the turbine housing and turbine wheel. Cooling down the housing will prevent the heat transfer to the turbine wheel-thru the shaft to seal and bearing.

The strong suit for the K27 design is the multiple sealing rings that prevent the migration of oil from the bearing housing to the turbine side. With proper breakin and cool down one can double the life of this turbocharger.