thermostat

[Rootie524]

should i be running a cooler thermostat in my 3100? i believe i have a 195 in now..should i put a 180 in..idk what the advantages/disadvantages are.

[robertisaar]

about the only advantages a lower temp stat has is that it will help prevent detonation, and if you happen to live in a hot climate, it should help prevent it from getting too hot while just sitting, but so would lower fan enable temps...

[Superdave]

180 is the lowest you should use.. and the tune needs to be adjusted for that.

[blowns10]

Yeah, if you use anything lower than 180 degrees, you're just wasting your time. It'll use up more fuel because the ECM will think the engine is cold and will probably end up running in open loop all the time. Besides that I wouldn't suggest running anything lower than 180. Either just use what you have or go to the 180 to prevent detonation, but cleaning and blending the combustion chamber would reduce hot spots and there would be no need to have a lower temp thermostat. Late.

[robertisaar]

i wouldn't say a lower temp stat would prevent closed loop... in most calibrations i've seen, the ECM wants to see a ~120*F coolant temp to allow it...

[Schmieder]

i wouldn't say a lower temp stat would prevent closed loop... in most calibrations i've seen, the ECM wants to see a ~120*F coolant temp to allow it...

And if you have a tuner, you can easily change that and tune for lower ECT's.

I run a 180 t-stat and have fan I set at 195*on/185*off, fan II set at 200*on/185*off.

should i be running a cooler thermostat in my 3100? i believe i have a 195 in now..should i put a 180 in..idk what the advantages/disadvantages are.

Like others said, I used 180 for the turbo install to help prevent detonation especially since the turbo increases IAT's.

I agree with 180. 195 is too hot and 160 is too cool unless you plan to run a serious high HP engine with lots of boost. Most people won't ever see that kind of power.

[Azrael]

Your engine is designed for certain amounts of thermal expansion over it's running life. It won't likely be much but there will be some accelerated cylinder wear over the long term.

[Superdave]

It's important to remember, just because your thermostat opens at 180 doesn't mean that's the hottest your engine will ever get.

I ran a 180 and saw 225+ at the track with the fan running all the time.

[Schmieder]

It's important to remember, just because your thermostat opens at 180 doesn't mean that's the hottest your engine will ever get.

I ran a 180 and saw 225+ at the track with the fan running all the time.

yup, a hot day, strong sun, WOT from 0-120 mph will definately heat things up.

I know the T-stat is also important to create pressure in the block to prevent boil over. How great of a pressure loss would occur with a 180* stat?

I may take a shot at the math but it seems like an interesting question. With heat comes pressures and loosing 15* would = some pressure loss. Not sure if it matters much.

[geoffinbc]

Cooler temps reduce power. PERIOD. You will see more power between 200*F and 220*F at 230*F your beginning to overheat so most engines run a safe margin and run around 200*F. At this temp the oil is thin and is causing less drag, fuel burns more completely so there is less waste and cleaner emissions and less horsepower is lost to the cooling system. Heat is power so don't put it into the coolant.

All car makers run hotter engines these days for the above reasons. All a cool thermostat is going to do is inhibit proper running of the engine. Also consider that water boils at 200*F so if there is any condensation in the engine from a cold damp morning it will all boil off once your engine reaches full temp.

[sprucegagt]

Every few months this topic keeps coming up, and every few months the same responses keep coming. I wonder if this should be a sticky?

[ssdurango]

My propane conversion manual says to use a cooler thermostat (160 or so). Propane is allready a vapor once it's been through the regulator so there is no need for more heat to completly burn it. In a boosted application, like mine, this can stave off pinging and detenation.

[blowns10]

Also consider that water boils at 200*F

Water boils at 212 degrees Fahrenheit, not 200 degrees.

Yes, definitely, this topic should be made into a sticky, enlighten me!!. Late.

[robertisaar]

Water boils at 212 degrees Fahrenheit, not 200 degrees.

Yes, definitely, this topic should be made into a sticky, enlighten me!!. Late.

if you want to get technical, PURE water boils at 212*F when not under pressure. pressure raises the boiling point significantly.

[blowns10]

Yes, pure water boils @ 212 degrees Fahrenheit, correct. And adding coolant increases the boiling point, yes you are correct. I could write for days about this stuff and I would be glad if someone would make this topic a sticky!!. Yes the engine can be made to run as hot as possible for best emissions. But heat (friction) is also the enemy, so you have to have a safe margin to work with, otherwise whatever you are running, be it differential fluid, transmission fluid, engine oils, brake fluid needs to be kept as cool as possible to keep the component working properly and to prevent overheating and warping or seizure of the component!!. Like I said, enlighten me!!. Late.