160 tstat in my 02 5.3 suburban

**tvaughn64** · 06-25-2008, 10:11 AM

I have installed the 160 stat and the temp is steady at around 185 but when I turn the air on it goes to about 208.is this normal

**Spaz** · 06-25-2008, 10:49 AM

Originally Posted by tvaughn64

I have installed the 160 stat and the temp is steady at around 185 but when I turn the air on it goes to about 208.is this normal

160 means it will open at 160 to start cooling instead of what ever the stocker is (probably 180)... yes that is normal for the temp to raise... your engine bumps the rpms (idle an way) up a bit to compensate for the AC pulling power away from other stuff...

**Spaz** · 06-25-2008, 11:42 AM

Originally Posted by Spaz

160 means it will open at 160 to start cooling instead of what ever the stocker is (probably 180)... yes that is normal for the temp to raise... your engine bumps the rpms (idle an way) up a bit to compensate for the AC pulling power away from other stuff...

my best guess any way...

**Tim the Tool Man** · 06-25-2008, 05:16 PM

Coolants should boil around 240/255F under pressure. No engine will run 185, at least not in Houston summers. Installing a colder stat only means the system can run there if the heat transfer is balanced. 208 is quite normal for an engine. Plus, your AC condensor is in front of your radiator which raises the air temp to the radiator, which accounts for a lot of the 23F rise in coolant temperature. The rest is in the extra horsepower to run the AC.

**SPRT2H** · 06-26-2008, 06:32 AM

do you have to make any other changes when running a lower t-stat ?

**'99 SLP#24** · 06-26-2008, 06:46 AM

On a vehicle with electric fans you would want to tune for the fans to come on earlier. However unless you've changed them on your Suburban you don't have e-fans so you don't need to change that.