160 thermostat or 180 thermostat???

[1990GMCSIERRA]

see this is whats getting me,i thought running cooler is better?
i mean i know alot but this one is getting me

 

[4x4chevy]

Well i live in florida and i dont go up north alot and i was thinking of getting the jet chip for that little more power and what to know. Which one would be better for the chip and would it kill me it i put it in the truck with stock till i get one.

 

[CodyB]

The engine was designed to run more efficiently at that temperature ala thermodynamics and such fun calculations. It was tuned by GM with these variables in the "window" that the stock thermo runs at...

 

[Aloicious]

see this is whats getting me,i thought running cooler is better?
i mean i know alot but this one is getting me

not really when it comes to ECT. now if you're talking about the intake air temp (IAT) then yes, cooler is always better (think intercoolers, MeOH/H2O injection, etc), but that does not translate to every facet of engine management. internal combustion engines are more efficient when they are warmer (up to a point obviously), when we're talking about coolant temp which flows through the head, the slightly warmer temp will give better fuel atomization in and around the combustion chamber, which will translate into better and more complete combustion, among other things. when it comes to efficiency, then with ECT, warmer = better (to a point, most engines are best right around 200*F, which is why stock T-stats are usually 195*).

the thing with thermostat temps and power is all about spark. here's some things to look at for anyone thinking about changing thermostat temps.
are you boosted? do you have advanced spark maps (tune)? how modified is the vehicle? are you getting detonation/ping/knock retard (KR)?

if you're not severely modified (I'm taking cam+heads+compression ratio increase, and/or boosted) then there is no reason to run anything colder than stock (195*). if you are severely modified then dropping the temp wouldn't hurt to combat any potential pinging. if you're getting a tune and want to advance the spark maps a little more than usual, you can get a cooler thermostat, but the gains you would see would be minimal at best, but you may also see a drop in efficiency running the lower temp sensor.

I personally wouldn't ever run a 160 unless I HAD to, I currently have a severely modified L31 which is also boosted, and run a 180* T-stat. which works great. now if I couldn't control KR with the 180, I might look at going to a 160 but for me that would be a last resort, I like my heater in the winter and a properly setup and tuned engine will combat KR more effectively than just using a different T-stat.

also remember that the thermostat temp doesn't have too much to do with how hot the engine acutally runs, that is more dictated by the radiator and overall cooling system health. the thermostat temp is simply what temp the T-stat OPENS at, not what temp the engine will RUN at.

to the OP, my advice, use the stock 195* T-stat. even if you live down south. if you're having cooling problems then upgrade the radiator like was mentioned earlier. I run a 454SS radiator in my '96 C1500.

 

[Fleeingpepper]

Mine came with a 160 and when one of my coolant hoses busted I changed out the T-stat to a warmer one cause it was ridiculous how cool it ran. I forgot which one Oreillys gave me. Either 180 or 195. My mileage didn't actually go up all that much so maybe it was just 180.
But definitely get the hotter one.

 

[1990GMCSIERRA]

everyone i kno use 160 and run great

 

[1990GMCSIERRA]

i switched to a 160 and runs way better

 

[Fleeingpepper]

How's your mileage now?

 

[1990GMCSIERRA]

****** so i went back to a 195 lol
it did run great with no issues tho,,other than the mpg's

 

[Fleeingpepper]

Haha yeah I didn't notice any difference in how it ran but my mileage was awful! The engine can't warm up enough to get to where it's most efficiently burning the fuel.