Okay so I had recently bought a 160' degree t-stat (not stant) for my 87' turbo. Upon furhter research I decided to go with a 180' , what exactly should I be reading for water temp, the car was cooling and coolant was flowing (no overflow or leaks) I was in between 150-180 about 165' and upon spirited driving around 180' but it would cool down right away. Is it overcooling? and why?
Note: I do have a a exhaust leak from my turbo flange to exhaust flange and am losing boost if that were to make a difference? Thanks for any help.

Edit** It was pretty cool out if about -1 degree celsius if that makes a difference

 

mine usually stays at about 180' a little higher when im running around of course. Are you just wondering about what it runs when sub freezing or do you have an upgraded cooling system

 

Nope system is stock, rad might be an upgrade but I don't think so, is it just because of the cooler weather?

 

Your car should still reach a place on the gauge and stay there.

A common cause of this is the thermostat being stuck open.

 

After I took out my AC condenser I noticed my temps rarely get above ~170-180 according to my Rtek. Even this last weekend drag racing my temps never got above 180. Before I took out the condenser I used to see quite a bit higher though, especially with prolonged uphill driving.

 

my temp is consistent it just seems odd that i'm sitting around 165-170 with a 180 t stat

 

your oil cooler t-stat may be stuck open. i disabled mine so it is always open and my temps are usually 1/8th on the gauge