I've never had a vehicle with a proper cooling system that would run over the rated temp of the thermostat except for momentarily exceeding it by about 5 degrees during the normal cycling of the thermostat.
ANY time that an engine exceeds the rated thermostat temp for an extended time (assuming the T-stat is working) indicates the engine is capable of producing more heat than the cooling system is capable of removing.
Ambient air temps should only come into play when it exceeds the design parameters of the cooling system, our old cars were probably not designed to work with ambient temps above about 120 degrees. Which can happen at road level in the southwest on a sunny day. That is nether a cooling system "problem" or a T-stat problem, it's operating the vehicle outside it's design parameters, would doubly apply to a modified engine, more HP generates more heat.
Many, many thousands of people over the decades have removed their 180 T-stats that were running at 200 degrees and replaced them with 160 T-stats to "make their engine run cooler" ... doesn't work of course, if the cooling system can not remove enough heat to maintain 180 degrees it certainly can't maintain 160.
|