Low temp thermostat

[David C. Allen]

I thought that the object of game was to keep the thermostat in the closed 
loop mode. It should only be in open loop during initial warm-up. The ECM 
can try to change engine operation during upper engine temperature 
excursions, but it can not change the outside temperature or the fact that 
you are stuck in traffic. In the Suburban 1227165 TPI project, I plan to 
change from a engine driven cooling fan to twin electric cooling units 
which I can control via the ECM. With air conditioning you could/will add 
heat to radiator because of the airflow path, the ECM knows head pressure 
and engine temp so it could short cycle the compressor, and add additional 
cooling to lower AC head pressure.

So I think the selection of a thermostat operating temp and strategies of 
how to keep the thermostat in a closed loop operation is a very important 
part of the gm ECM discussion. I would like to hear more!

David