Coolant Temp Advice
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Coolant Temp Advice
Hey guys, just wanted to get some advice on my temps for my 02 Z06. I have an A&A supercharger kit going on very soon and I just wanted to see if I need to address the cooling system before that happens. The only mods to the car right now is a halltech intake and long tube headers.
I live in Phoenix, so the ambient temps are quite high during the summer months. Today was about 104 outside and I have about a 30 minute drive home from work, all city. For the first half of the way home, I kept it pretty tame, and under those conditions my coolant varied between 200-207. For the last leg of my trip, I drove a bit more spirited. Driving with a heavier foot, I was reading 217-227.
My question is, are these temps in line with what you'd expect driving in a hot weather climate? Should I consider these to be too high, especially with a supercharger kit going on soon? Should I think about dropping to a lower thermostat and getting my fans reprogrammed?
Sorry if this topic has been beaten to death. This is my first corvette and I just want to sure about the way the car runs. Any advice or opinions are greatly appreciated.
I live in Phoenix, so the ambient temps are quite high during the summer months. Today was about 104 outside and I have about a 30 minute drive home from work, all city. For the first half of the way home, I kept it pretty tame, and under those conditions my coolant varied between 200-207. For the last leg of my trip, I drove a bit more spirited. Driving with a heavier foot, I was reading 217-227.
My question is, are these temps in line with what you'd expect driving in a hot weather climate? Should I consider these to be too high, especially with a supercharger kit going on soon? Should I think about dropping to a lower thermostat and getting my fans reprogrammed?
Sorry if this topic has been beaten to death. This is my first corvette and I just want to sure about the way the car runs. Any advice or opinions are greatly appreciated.
Le Mans Master
Joined: Aug 2005
Posts: 5,375
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From: CA.
St. Jude Donor '13-'14-'15
The # 1 fan has a turn of speed of 35 MPH
The #2 fan has NO turn off speed and is strictly commanded by coolant temps
ALSO In a stock tune the #1 fan will not come on until the coolant reaches 226* and OFF at 219*
#2 fan on at 235* and off at 227*
Both of these settings are way to late even with a stock thermo of 195*
YES I would especially with boost install a lower thermo---I like the 160* the best--the engine will never run that cold
Best fan settings with a 160* thermo would be like
#1 on at 195*
#1 off at 190*
#2 fan on at 205*
#2 fan off at 196*
This will keep your operating temps always in the 190-200 range
To take advantage of a cooler thermo you MUST adjust your fan settings or it will not work-------217-220 is in my opinion just plain too HOT---
The #2 fan has NO turn off speed and is strictly commanded by coolant temps
ALSO In a stock tune the #1 fan will not come on until the coolant reaches 226* and OFF at 219*
#2 fan on at 235* and off at 227*
Both of these settings are way to late even with a stock thermo of 195*
YES I would especially with boost install a lower thermo---I like the 160* the best--the engine will never run that cold
Best fan settings with a 160* thermo would be like
#1 on at 195*
#1 off at 190*
#2 fan on at 205*
#2 fan off at 196*
This will keep your operating temps always in the 190-200 range
To take advantage of a cooler thermo you MUST adjust your fan settings or it will not work-------217-220 is in my opinion just plain too HOT---
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Ya I forgot to mention that the ac was definitely on. That was kind of my train of though as well. With boost coming soon it would be smart to cool the engine down. It would be a perfect time for me to install the tstat as well, since it will be on the dyno getting a tune I can have the fans tuned at the same time.
I've read that some people say 160 is too low. It's my understanding that it's not fully open at 160, but more like 175 or so. Is that correct? I know running the engine down too low could cause issues.
I've read that some people say 160 is too low. It's my understanding that it's not fully open at 160, but more like 175 or so. Is that correct? I know running the engine down too low could cause issues.
Drifting
Joined: Oct 2002
Posts: 1,773
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From: SoCal
I'm in the thinking it is a bit too low (personal preference). I have an A&A kit on my car with the stock t-stat. I have my fans set at #1 fans 206-196. #2 fans at 217-207. I am running the dewitts radiator and SPAL fans though. Keeps the car in the 190-210 range usually. Don't recall a time since where it has gone over 220 in 100+ temps and A/C on. The fans is a nice upgrade. Really helps keep the temps down. Radiator helps too but not as much from what I have seen.
Le Mans Master
Joined: Aug 2005
Posts: 5,375
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From: CA.
St. Jude Donor '13-'14-'15
Ya I forgot to mention that the ac was definitely on. That was kind of my train of though as well. With boost coming soon it would be smart to cool the engine down. It would be a perfect time for me to install the tstat as well, since it will be on the dyno getting a tune I can have the fans tuned at the same time.
I've read that some people say 160 is too low. It's my understanding that it's not fully open at 160, but more like 175 or so. Is that correct? I know running the engine down too low could cause issues.
I've read that some people say 160 is too low. It's my understanding that it's not fully open at 160, but more like 175 or so. Is that correct? I know running the engine down too low could cause issues.
Remember that the combustion chamber temps and engine oil temps happen 1st-- and the cooling system is there to cool everything down after the heat is created----Cooler radiator temps have little affect on the temps created by the engine or oil--it simply cools it down afterwards----I have run a 160 thermo on all my 8 Corvettes and numerous other LS applications and it the engine oil temps are always in the 200* range----Old school thought was that you wanted the oil to be hot in order to boil off any moisture in the oil-- but having a cooler engine has little affect on oil temps and will never allow them to run extremely cold------Plus a cooler engine makes all the rubber hoses and electrics last longer--On an auto trans it also cools the trans better-----and finally it prevents the IAT temps from spiking out of control which can create timing from being removed from false high underhood temps
Le Mans Master
Joined: Mar 2011
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From: Columbia SC
I disagree with the description of how the fans work above. Both fans either run in low speed or high speed or they are OFF. Here is the factory design.
Factory temp settings are low speed on at 226 degrees and off at 219 degrees. High speed on at 235 degrees and revert to low speed at 226 degrees. As stated both fans run at low speed and high speed and fans are commanded off by the PCM when the vehicle speed exceeds 35mph.
You can force low speed operation at 185 degrees by turning on the AC. High speed operation with AC on is still 235 degrees.
Thermostat temp selection is not as critical in todays engines but they were in years past. There is lots of technical info graphing how colder settings really do increase cylinder wall wear. That's why in my 426 Hemi I did not go with s 160 F one and used the 180F.
Mr. Sam
Mr. Sam
Factory temp settings are low speed on at 226 degrees and off at 219 degrees. High speed on at 235 degrees and revert to low speed at 226 degrees. As stated both fans run at low speed and high speed and fans are commanded off by the PCM when the vehicle speed exceeds 35mph.
You can force low speed operation at 185 degrees by turning on the AC. High speed operation with AC on is still 235 degrees.
Thermostat temp selection is not as critical in todays engines but they were in years past. There is lots of technical info graphing how colder settings really do increase cylinder wall wear. That's why in my 426 Hemi I did not go with s 160 F one and used the 180F.
Mr. Sam
Mr. Sam
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My main goal is to avoid detonation during the summer months when my ambient temps can see in excess of 115 degrees. Spirited driving(especially with a blower), and for that matter idiling as well, in that weather definitely puts a strain on the cooling system.
Now in your guys' opinion, what would be the correct way to approach the issue? Would it be better to send the coolant to the radiator at a lower temperature via a new thermostat? Let the radiator attempt to cool a lower temp coolant? Or upgrade to a new radiator and fans and be able to handle the higher temps they would see with a stock thermostat in place? Maybe it's both? Or maybe I'm dead wrong on the whole issue. That's the glory about the internet, get to chat with guys who have been there and done that
.
Now in your guys' opinion, what would be the correct way to approach the issue? Would it be better to send the coolant to the radiator at a lower temperature via a new thermostat? Let the radiator attempt to cool a lower temp coolant? Or upgrade to a new radiator and fans and be able to handle the higher temps they would see with a stock thermostat in place? Maybe it's both? Or maybe I'm dead wrong on the whole issue. That's the glory about the internet, get to chat with guys who have been there and done that
.
Le Mans Master
Joined: Feb 2012
Posts: 6,644
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From: OK
From the research on the forum I would say the most important temp is your engine oil... it needs to be around 200.
Your going to find heated (pun intended) discussion about how hot is too hot, and how cool is too cool, and the reality is there is pro's and con's for both... and I want to be in the middle somewhere. About 190 ish...
It depends a LOT on where you live... in your sector of the country, I wouldn't worry much about too cool... IMHO
So, I'd say BOTH. stat and reprogram
If you lived in Michigan or Alaska the rules would change...
Your going to find heated (pun intended) discussion about how hot is too hot, and how cool is too cool, and the reality is there is pro's and con's for both... and I want to be in the middle somewhere. About 190 ish...
It depends a LOT on where you live... in your sector of the country, I wouldn't worry much about too cool... IMHO
So, I'd say BOTH. stat and reprogram
If you lived in Michigan or Alaska the rules would change...
Last edited by 73Corvette; Oct 2, 2015 at 11:29 AM.
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From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
Lots of good advice and comments here, but the easiest, and quickest way, to answer your question, would be to simply call Andy at A&A and ask him for his recommendations. 
Drifting
Joined: Dec 2011
Posts: 1,422
Likes: 118
From: San Gabriel Valley California
St. Jude Donor '14-'15
I agree!
I've had a couple of setups with A&A, and can't say enough good things about them.
Call Andy (or Josh), tell them you have one of their kits ordered, where you live, and your concerns about operating temps.
They will advise you of options you can consider.
I would advise, that you have A&A install the big Dewitts radaitor, along with your SC install. (or whoever you're having do the install)
They have them, and have already figured out how to make them fit with their intercooler. This, will help you lower temps, along side Andy will 'tune' in new starting temps for your fans to kick on, when he dynos/tunes your car.
Good choice, with A&A. You'll love it after the install.
Don
Safety Car
Joined: Jan 2015
Posts: 3,830
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From: Rocky Mountains
I live in Phoenix. My temps are similar to yours. The coolant hit 230 today. Hauling *** on the freeway. it went as low as 192. But it goes up fast when you're crawling through traffic. In this climate, I would consider it mandatory to upgrade the cooling system if you install a supercharger.