Well I changed out my 160 temp switch on the intake to a 180 I let the truck get to temp which runs 180/185 normally instead of fans running all the time they came on at around 180 like it should have then dropped temp down to about 175 great fans r not running all the time what I was trying to achevie. So then I took out 180 thermostat and replaced it with a 160 thinking it would run even cooler wrong now granted I did not put back any antifreeze straight water now fans came on at 180ish and could not cool her down temp kept. Climbing to 210 before shut her off. Would antifreeze make that much diff?. Would I put back 180 stat? Or should I maybe put a 190 stat in by the way it has 12" duel fans on it pushing no other way with out lots of $. And I do not have a switch for fan control . But I was happy wit it cutting off at 180 seemed to go. Prob of fans running all the time any help would great its a 59 250 4x4 been moded with a 460 c6 three auto Trans thang agian.

 

Podds Something does not sound right, after changing to 160 thermostat. You said the temp climbed to 210? Did you notice the coolant start to flow in to the tank as the temp came up? I'm wondering if the thermostat is stuck , blocked or in backwards. Antifreeze wont make that sort of difference (nothing cools better than water but you need the added properties of the antifreeze).
If it worked well after raising the fan control thermostat, why not just go back to the 180 thermostat, if you raise the coolant thermostat to 190 you will be back to the problem of coolant thermostat higher than fan thermostat.
Clear as mud?

 

I will try to make it a little muddier. a 160 degree thermostat will open at 160 degrees. it may or may not cause the engine to run hotter or colder. it seems to me it would depend on how the engine is working in relationship to the radiator. is it a stock radiator? aftermarket? think of it this way, if you took the thermostat out should it run really cool? no, because the water will run through the radiator so fast that no heat can be pulled out of the water. its all got to work together, radiator, thermostat, fan etc. with a 460 and un-known radiator, and two pusher fans you are shooting in the dark. I'm with Wally, put the 180 back in and be done. don't forget the antifreeze before it gets cold again. just my 2 cents worth, and with the dollar falling as fast as it is, more like half a cent.

 

I'm with Thundersnow...a 160* thermostat doesn't mean it will keep it at 160, just that it opens at 160. I've always had good luck with 180.