Bill,

I respectfully disagree. The thermostat is the control mechanism (the only one) for the cooling system. The radiator is designed be able to satisfy what the thermostat asks of it! A properly functioning cooling system should maintain temperature near that of the thermostat. It has no bearing on engine characteristics.

The only reason a modern automotive system runs at 212&deg is because it was designed in Detroit to run at 212&deg. If it has adequate cooling capacity and you install a 175&deg 'stat', it would probably run at that temp! That's how I see it.

Stuart