160* Thermostat?
#3
I have no idea if one is available. I think it would cause the ECU to run slightly rich. Old time hot rodders used 140 and 160 (or no) thermostats to try and keep monster motors from overheating. I am sure that there is a fuel set up to accomodate lower op temps but with the EPA regs so strict, the 195 operating temp is chosen as optimal. You did not ask for opinions, only sources but I think the change would provide very little, if any benefit.