New thermostat
Thread Starter
Racer
Joined: Sep 2016
Posts: 252
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From: O'Neill (Home of St. Pat's Weekend) NE
New thermostat
OK I have searched and looked but all I have come up with is confusing opinions. Just what is everyone's idea on "Leaving the stock temp thermostat in or going with a lower temp one, IE 160 degree or so and reprogramming the fans?" Just want to know why in either case? The car is a "Sunday Driver". Sorry if I'm
Le Mans Master
Joined: Sep 2014
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From: Kelowna BC
If your car is not overheating I don't see much point in a lower temp thermostat. Once the thermostat is open, its open. 160deg just opens at a cooler temp (bad for emissions reasons).
The fans being on 10deg lower is something I had done, as we can hit over 100F here, and I daily my Z spring, summer and fall.
The fans being on 10deg lower is something I had done, as we can hit over 100F here, and I daily my Z spring, summer and fall.
Race Director
Joined: May 2003
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From: Iowa
St. Jude Donor '03 thru '26
Is your car modified? IE. Does it have an intercooler? If not, then no, 180 would be fine and so are the factory settings. I think the engineers know more about the C5 than anyone on here knows.
1/4 mile/AutoX
Joined: Jun 2014
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From: Buffalo Texas
180 stat and tuned to have the fans come on earlier, runs 192 (90% of the time and highest I have ever seen (103 outside temp in traffic) 207 !!! the debate goes on forever, we have three Vettes all with cooler thermostats and ALL run cooler !!!! I do NOT want mine running above 220 EVER !!!!!!!
Last edited by Pounder; Nov 11, 2017 at 05:16 PM.
Drifting
Joined: Nov 2016
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From: SF Bay Area
If your car is stock, there is no point in going to a lower thermostat. Lowers fuel efficiency among other things.
If you're running higher compression, more advanced timing, or anything else that increases the chances of detonation, a lower temperature thermostat can help fight against detonation. Of course, you should be running higher octane fuel as well in this case.
If you're running higher compression, more advanced timing, or anything else that increases the chances of detonation, a lower temperature thermostat can help fight against detonation. Of course, you should be running higher octane fuel as well in this case.
Thread Starter
Racer
Joined: Sep 2016
Posts: 252
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From: O'Neill (Home of St. Pat's Weekend) NE
And the debate goes on!! I would think that the engineers would know better than the "average Joe" but it seems like 210 plus even for a short time, IE in traffic would be a "little" hot. But I am old school and remember a 160 t stat was the norm for an engine. Maybe a gauge that just showed C--I--H instead of degrees would make it easier to live with IE "dumb it down" IDK ?
Drifting
Joined: Nov 2016
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From: SF Bay Area
Materials, construction design, and computer control have advanced significantly. Anyone familiar with the Carnot cycle knows that the higher temperature you run, the more efficient the engine is and the more energy that can be extracted out from the same amount of fuel. Higher compression is one method of simulating higher temperature. Same with forced induction. The limitation is essentially due to the materials, and I'm sure GM tested it to make sure the block can tolerate those temperatures.
There is a C5 corvette that went something like 770,000 miles on the original engine. Dealer maintained, so I'm sure they kept the original 190 degree thermostat.
There is a C5 corvette that went something like 770,000 miles on the original engine. Dealer maintained, so I'm sure they kept the original 190 degree thermostat.
Thread Starter
Racer
Joined: Sep 2016
Posts: 252
Likes: 103
From: O'Neill (Home of St. Pat's Weekend) NE
Materials, construction design, and computer control have advanced significantly. Anyone familiar with the Carnot cycle knows that the higher temperature you run, the more efficient the engine is and the more energy that can be extracted out from the same amount of fuel. Higher compression is one method of simulating higher temperature. Same with forced induction. The limitation is essentially due to the materials, and I'm sure GM tested it to make sure the block can tolerate those temperatures.
There is a C5 corvette that went something like 770,000 miles on the original engine. Dealer maintained, so I'm sure they kept the original 190 degree thermostat.
There is a C5 corvette that went something like 770,000 miles on the original engine. Dealer maintained, so I'm sure they kept the original 190 degree thermostat.
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stock stat and have the fans programmed to turn on sooner, that is all you need to do to make the car run cooler at idle with the ac which is when you really need it... putting in a 160 stat will do nothing to the temps at idle unless you have the fans reprogrammed as well... a 160 stat will make the car run cooler when cruising which is the opposite of what you need and depending on how cool it gets in your area the car could run too cool or take a long time to warm up so your heater may also suffer... I'm not a fan of 160's personally
1/4 mile/AutoX
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From: Buffalo Texas
why do ALL the other LS based vehicles run under 210 all the time ??????????????????????????
Drifting
Joined: Nov 2016
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From: SF Bay Area
1/4 mile/AutoX
Joined: Jun 2014
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From: Buffalo Texas
my point exactly !!!! the C 5 programmed to run hotter than all other LS's !!!!!! wonder why the C 5's leak oil, have vibration damper fails, waterpump fails, etc ?????????? What I KNOW is no performance minded person wants their engines running hot !!!! What I do know is heat is the major enemy of everything on a Vehicle !!! (especially engine and trans) !!!! Do as you wish, I will run mine at a cooler temp, and will have a whole lot less issues than others may have !!!!!
Drifting
Joined: Nov 2016
Posts: 1,660
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From: SF Bay Area
my point exactly !!!! the C 5 programmed to run hotter than all other LS's !!!!!! wonder why the C 5's leak oil, have vibration damper fails, waterpump fails, etc ?????????? What I KNOW is no performance minded person wants their engines running hot !!!! What I do know is heat is the major enemy of everything on a Vehicle !!! (especially engine and trans) !!!! Do as you wish, I will run mine at a cooler temp, and will have a whole lot less issues than others may have !!!!!
C5s leaking oil can be attributed to other things, one of which is the extremely poorly thought out PCV design. Wear and tear is debatable, and has not really been proven one way or the other. What has been proven is that too low operating temps can cause INCREASED wear and tear.
Last edited by Tsumi; Nov 10, 2017 at 05:19 PM.
1/4 mile/AutoX
Joined: Jun 2014
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From: Buffalo Texas
Are you just so eager to prove me wrong that you are completely incapable of reading? I said C6 Corvette, not C5.
C5s leaking oil can be attributed to other things, one of which is the extremely poorly thought out PCV design. Wear and tear is debatable, and has not really been proven one way or the other. What has been proven is that too low operating temps can cause INCREASED wear and tear.
C5s leaking oil can be attributed to other things, one of which is the extremely poorly thought out PCV design. Wear and tear is debatable, and has not really been proven one way or the other. What has been proven is that too low operating temps can cause INCREASED wear and tear.
1/4 mile/AutoX
Joined: Jun 2014
Posts: 11,440
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From: Buffalo Texas
Are you just so eager to prove me wrong that you are completely incapable of reading? I said C6 Corvette, not C5.
C5s leaking oil can be attributed to other things, one of which is the extremely poorly thought out PCV design. Wear and tear is debatable, and has not really been proven one way or the other. What has been proven is that too low operating temps can cause INCREASED wear and tear.
C5s leaking oil can be attributed to other things, one of which is the extremely poorly thought out PCV design. Wear and tear is debatable, and has not really been proven one way or the other. What has been proven is that too low operating temps can cause INCREASED wear and tear.
Drifting
Joined: Nov 2016
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From: SF Bay Area
1/4 mile/AutoX
Joined: Jun 2014
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From: Buffalo Texas
I would think someone as smart as you would know I was referring to non-corvette vehicles ???? after all the Vette is supposed to be a performance car not my pickup ???
Last edited by Pounder; Nov 10, 2017 at 05:37 PM.
Race Director
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From: Iowa
St. Jude Donor '03 thru '26
Pounder, do you have any engineering degrees? I don't so I'm going to rely on those Chevy C5 personal that do. I'm sure there are reasons that you do not understand that they choose the thermostat and fan turn-ons settings.
1/4 mile/AutoX
Joined: Jun 2014
Posts: 11,440
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From: Buffalo Texas
yep the same engineers that designed the rocking seats, that great shifter (manual) and the auto shifter that breaks more than it should ??? OH what about that GREAT column lock feature ???? (I could go on all day) Sometimes working on them your whole life gives you a much better in sight to things !!!! Like I stated run yours hot I don't care !!!!
Burning Brakes
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From: Motor City, MI
My tuner told me to install a 160 stat and he programmed the fans to turn on at 192. Even in stop and go mid summer 210 is about as hot as it gets. It's generally right around 190-200 during typical driving.
Dr. Phil is a bit of a legend and I trust him...he was engineering the LS1 before the first one left in a C5, he's supported GM's factory race efforts over the years, tunes for Katech, etc. He turned those fans on earlier when the car had only a CAI and cat back. He retuned it after headers/cam/heads and didn't touch the fan settings. So he likes those setting basically from stock to mild heads/cam.
Before he tuned the car when it was bone stock the car would get into the 230s on a hot day and seemed to stumble a bit when it was that hot. Erroring on a little cooler rather than hotter seems obvious to me, but I don't want to pretend to know more than I do.
Dr. Phil is a bit of a legend and I trust him...he was engineering the LS1 before the first one left in a C5, he's supported GM's factory race efforts over the years, tunes for Katech, etc. He turned those fans on earlier when the car had only a CAI and cat back. He retuned it after headers/cam/heads and didn't touch the fan settings. So he likes those setting basically from stock to mild heads/cam.
Before he tuned the car when it was bone stock the car would get into the 230s on a hot day and seemed to stumble a bit when it was that hot. Erroring on a little cooler rather than hotter seems obvious to me, but I don't want to pretend to know more than I do.