160 tstat

[tvaughn64]

running at about 185.Then turn air on goes up to 208 is this normal

[mrr23]

did you set the fan on/off settings lower than stock?

[WS6ICK]

set fan1 on @ 181 and off @ 178. Fan 2 on @ 183 and off @ 178. Of course you need a tuner to do this.

[crazyhorse]

I would like to know about using a 160 t-stat with a clutch fan,what would I expect in temp. changes.

[Firebirdjones]

I would like to know about using a 160 t-stat with a clutch fan,what would I expect in temp. changes.

On a mechanical fan,,,simply changing the thermostat is all thats needed as far as temperature. The rest will take care of itself so long as the radiator and mechanical fan are up to the task.

[crazyhorse]

so it's gonna run 180-195.i see post that it is not a good idea and it'll cause excessive piston wear.but cooler is better.thanks for your answer so quickly.

[Rob Mellinger]

160 thermo, runs about 162 all day long down the highway, outside temp. dosent seem to matter.

[Frost]

160 thermo, runs about 162 all day long down the highway, outside temp. dosent seem to matter.

I *NEVER* see them run that cool... You must be looking at the factory guage.

I don't typically have fan 1 run before 185-187 even on 160-stat'd cars or many of them will end up running fan1 nearly all of the time. I don't use a canned number but rather log and see where the engine is operating at cruise (when fans aren't needed) and kind of go from there on fan numbers.

[Rob Mellinger]

Yes, thats looking at the factory gauge. Are they not that accurate? Computer set to run fans for a 180 thermostat. I found, like you said, set on 160 thermo. fans ran almost all the time.

[Frost]

The 99 and up guages are completely dummied out and have operational "zones". I see you are a 98. They have their own sender but the guages are quite inaccurate even though not dummied like the 99-up.

[Firebirdjones]

Frost is right on the money. I found this out as well while logging, these 160 stats don't operate in the range they advertise. They are actually much closer to 172 degrees roughly,,,which makes fan settings touch and go.
This is somewhat a pet pieve of mine that Frost and I discussed here many times.

[Khaotic]

so it's gonna run 180-195.i see post that it is not a good idea and it'll cause excessive piston wear.but cooler is better.thanks for your answer so quickly.

On newer Gm its not better to run cooler temps, you want to run in the 180 to 200 degree due to thermal efficancy besides going to cool on the thermostat opening, temps tends to keep the pcm in the warm up routine skewing targeted fuel delivery, unless you have had your car tunned to avoid excess enrichment.

Theirs a scale in the pcm that it looks at for adding fuel vs. temps and if it thinks your still warming up it will be rich. So a tune is required to correct.

[partemisio]

As a note for people that don't know; The temperature rating of the thermostat is when it starts to open. So, a 160* thermostat starts opening at 160*.

[mrr23]

On newer Gm its not better to run cooler temps, you want to run in the 180 to 200 degree due to thermal efficancy besides going to cool on the thermostat opening, temps tends to keep the pcm in the warm up routine skewing targeted fuel delivery, unless you have had your car tunned to avoid excess enrichment.

Theirs a scale in the pcm that it looks at for adding fuel vs. temps and if it thinks your still warming up it will be rich. So a tune is required to correct.

we've been over this one in a previous 160 tstat thread. factory setting for closed loop operation is 92*F.



there are two other tables

first one PN/ Drive Enrichment Initial Adder vs ECT. has no effect after 89*F.



second one is after start enrichment initial adder vs ect. depending on startup temp, the multiplier is about .250. it has a delay of up to 100 engine revolutions with a decay every 4 engine revolutions at a rate of about 0.9639




so, again, myth busted.

[Khaotic]

Here is a link, about running differant Thermostats, mid way down Ed Wright and Dan from Massport, Explains pretty good about engine temps, Also Greg Danish teaches a good class on this and how it skews your reading threw your targeted fuel delivery along with Nate Tovey.

http://www.ls1tech.com/forums/showthread.php?t=937760

I will have to do a search and readup on what was previous posted. But check out the link its pretty good.

[mrr23]

Here is a link, about running differant Thermostats, mid way down Ed Wright and Dan from Massport, Explains pretty good about engine temps, Also Greg Danish teaches a good class on this and how it skews your reading threw your targeted fuel delivery along with Nate Tovey.

http://www.ls1tech.com/forums/showthread.php?t=937760

I will have to do a search and readup on what was previous posted. But check out the link its pretty good.

that thread only talks about the LSx motor making more power at a higher operating temp. dyno proven, but no evidence presented. i run a 170* tstat and my daily driving temps are 180-190. fans settings are in the 170-175 range. the tstat is nothing more than a doorway for water to start moving. there are other factors to keep the water at that temp.

[Firebirdjones]

As a note for people that don't know; The temperature rating of the thermostat is when it starts to open. So, a 160* thermostat starts opening at 160*.

That is correct for most thermostats. BUT,,,,the LSx 160 thermostat (LS1 in particular) does not start to open until around 172-173 degrees,,,I can log with HPtuner and watch it. Even had it in a pot of hot water with a probe and found the same results.

The LS1 thermostats that are advertised to operate at 160 degrees don't start actually opening until 172-173 and are fully open around 175-176 degrees,,,,therefore both of my LS1 Fbodies actually operate at an engine temp close to 180 degrees while moving down the road and logging,,,so fans have to be set accordingly otherwise they run continuously.

Unfortunately they just don't open when advertised due to design of the stat,,,,, thats about as good as it gets. Unlike the themrostats for older Gen 1 or Gen 2 small or big block chevys that actually work at 160-163 degrees.

[mrr23]

Here is a link, about running differant Thermostats, mid way down Ed Wright and Dan from Massport, Explains pretty good about engine temps, Also Greg Danish teaches a good class on this and how it skews your reading threw your targeted fuel delivery along with Nate Tovey.

back on this, i saw nowhere in that thread about how having a lower temp tstat skews readings for your targeted fuel delivery if your engine temps aren't in the 180* range. the tables that have to do with enrichment based on ECT either don't affect the fuel delvery after 89*F or after x amount of time after startup.

if anything, they are talking about thermal dynamics and friction due to running cooler temps, not fuel delivery via the PCM waiting for a certain engine temp. closed loop happens at 92*F and has no affect at WOT throttle for additional fueling.

[Khaotic]

back on this, i saw nowhere in that thread about how having a lower temp tstat skews readings for your targeted fuel delivery if your engine temps aren't in the 180* range. the tables that have to do with enrichment based on ECT either don't affect the fuel delvery after 89*F or after x amount of time after startup.

if anything, they are talking about thermal dynamics and friction due to running cooler temps, not fuel delivery via the PCM waiting for a certain engine temp. closed loop happens at 92*F and has no affect at WOT throttle for additional fueling.

Oops did have a type O, mrr23 I ment to talk about Thermal dynamics, and not about the Thermostat on the last post, good catch will pay more attention to my wording . Sleep deprived and smelling to much cam2 this week LOL.

[mrr23]

no problem