So, say you have installed a 160 degree thermostat... If the fans are switched on will the engine stay at or about that temp or hang around 200. Just curious if it would be worth my time.

Thanks

 

It depends on the atmospheric air temperature. C4 radiators were sized to get rid of heat fast enough maintain 185 to 195 F coolant temps over 35 mph depending on what year C4, early years have 195 stats, later years have 185 stats. In very cold winter climates, the radiator can get rid of much higher heat and your coolant could run 160 F, but outside of very cold winter temps, a 160 stat will stay wide open and the coolant temp will stabilize where the radiator gets rid of heat as fast as the engine makes it and this will be close to 185 to 195 F.
The cooling fans are intended for under 35 mph and they can only keep the temp below their turn on temperature which is 228 F for the main fan and 238 F for the auxilliary fan. The fans mainly come on at stop lights and will turn off when you get underway.
The 160 stat discussion has raged many times and many advocates of using 160 stats admit that their coolant temps are around 190 - 195 F when they are underway, but you cannot convince them that their 160 stat which is wide open (just like their factory 195 stat) at that coolant temp had any responsibility for those coolant temps.
Install a 160 stat, wire your fans so they stay on all the time and then honestly report what your coolant temperature runs. Then you will convince yourself and you won't have to decide who is correct in their assesment of how C4 cooling systems were designed !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!

 

My fans turned on manually can hold the coolant at 175 right where the tstat I had opened, on a hot day at idle.


I'm sure your fans if you had them running all the time could hold the coolant right at 160-165 with that 160 stat in there. Maybe lower without it.

But what would be the point?