highest coolant temps
Thread Starter
Instructor
Joined: Sep 2007
Posts: 117
Likes: 2
From: near Scranton, PA
highest coolant temps
Can anyone post their experience with highest coolant temps during high performance driving/stressful situations. What's "normal" or expected for our cars under strain or with spirited driving? I just modified my shroud to accept the Vararam and am curious to see if my temps go too high. I've always been afraid of high engine temps.
Racer
Joined: Mar 2006
Posts: 464
Likes: 2
From: Dallas TX
St. Jude Donor '12, '14-'15, '17, '20
My car usually runs pretty cool. I have 160 t-stat and Z51 with oil cooler. Highest I have seen for coolant is 230 and I was in stop in go traffic for an hour in 100 degree heat.
Drifting
Joined: Apr 2005
Posts: 1,757
Likes: 484
From: Portland Oregon
My 2005 A4 without Z51 runs about 199 to 205 normally. I don't really know what the high has been since I usually leave the DIC on the oil temp most of the time (which runs around 216 to 236 depending on the type of driving I do).
Pro
Joined: Jan 2008
Posts: 573
Likes: 1
From: Ohio
Yep, I keep the DIC on oil temp aswell. I would say get a 160 thermostat if you are worried about temps. 
Pro
Joined: Sep 2005
Posts: 528
Likes: 0
The service manual states that "the IPC illuminates the COOLANT OVER TEMP indicator in the message center when the following occurs:
The PCM detects that the engine coolant temperature exceeds 124*C (256*F)."
Also if you look at your temperature gauge you'll see that the line at 255* is a red line indicating the temp is too high.
There is an article in the August issue of Vette magazine about installing an electric water pump. The article states: "According to Meziere, for the typical Corvette LS, you probably want to run a little warmer than you would on an iron block engine, so we recommend a thermostat with a near stock temperature be chosen."
The PCM detects that the engine coolant temperature exceeds 124*C (256*F)."
Also if you look at your temperature gauge you'll see that the line at 255* is a red line indicating the temp is too high.
There is an article in the August issue of Vette magazine about installing an electric water pump. The article states: "According to Meziere, for the typical Corvette LS, you probably want to run a little warmer than you would on an iron block engine, so we recommend a thermostat with a near stock temperature be chosen."
Le Mans Master
Joined: Mar 2002
Posts: 5,253
Likes: 50
From: Sandy Eggo Calif.
St. Jude Donor '06-'07-'08-'09-'10-'11-'12, '16
I'm sure they mean that for a stock engine. If it's modified with a tune, a 160 is the consensus. Today it was HOT in San Diego. My DIC said 104 for an outside temp. and in stop and go, my coolant got up to 210. 190 on the freeway.(160T with a CoW tune)
Race Director
Joined: Sep 2007
Posts: 16,557
Likes: 2,106
From: Peoria/Phoenix AZ
C6 of Year Finalist (performance mods) 2019
I had a thread about adding a supplemental fan, because my temps were near 220 with 110-114 ambiant. I guess I was over-reacting.
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Thread Starter
Instructor
Joined: Sep 2007
Posts: 117
Likes: 2
From: near Scranton, PA
Thanks to all of you who posted real-world numbers. That's what I was actually looking for (I know what the gauge looks like and what the manual says). I wanted a benchmark to compare to and to see what others experience. I also thought it might be an interesting topic. I must admit I am not sure how to interpret the important differences between coolant and oil temps.
Pro
Joined: Sep 2005
Posts: 528
Likes: 0
The reason your temp did not go above 210 in stop and go traffic is not because of the thermostat. The reason is that the fan speed has been adjusted to run faster at lower temps. If the fan speed had not been adjusted the temp would have gone higher even if you had a 120* thermostat.
Last edited by Pozzo; Jun 20, 2008 at 11:53 PM.
Pro
Joined: Sep 2005
Posts: 528
Likes: 0
Thanks to all of you who posted real-world numbers. That's what I was actually looking for (I know what the gauge looks like and what the manual says). I wanted a benchmark to compare to and to see what others experience. I also thought it might be an interesting topic. I must admit I am not sure how to interpret the important differences between coolant and oil temps.
Racer
Joined: Mar 2006
Posts: 464
Likes: 2
From: Dallas TX
St. Jude Donor '12, '14-'15, '17, '20
After adding heads/cam, the car runs coolant 180-184 cruising on the highway at 70-100.
If I get stuck in traffic, it will go to 195-199, but usually never passes 200 since the fans come on. However, if ambient temps are hot 90-100+, coolant will definitely pass 200 and can go into 220's.
Former Vendor
Joined: Aug 2005
Posts: 5,774
Likes: 0
From: Loganville GA
I saw 255 on the gauge at Barber Motorsports park last month. I also burned out the bearing on my supercharger. I didn't look at the digital readout, but I had 289 on my oil temp.
Needless to say, I replaced the supercharger and have a larger radiator/oil cooler now.
Needless to say, I replaced the supercharger and have a larger radiator/oil cooler now.
Pro
Joined: Sep 2005
Posts: 528
Likes: 0
The 160* stat has nothing to do with the temperature reached in stop and go traffic for an hour in 100* heat. The temp reached under this condition is not affected by the thermostat.
Thread Starter
Instructor
Joined: Sep 2007
Posts: 117
Likes: 2
From: near Scranton, PA
But this doesn't explain to me the differences between oil and coolant temps as I mentioned in the post. I am thinking that oil temp generally runs higher and the heat is transferred to the coolant/antifreeze to be dissipated by the radiator. Pardon my novice but I am not an expert in this area. Can you elaborate on this?
Drifting
Joined: Feb 2007
Posts: 1,537
Likes: 1
From: Southlake Texas
Drove from Dallas to Houston this week (LS3). Average speed was about 75 mph for three hours and the ambient temperature was near 100F (road surface was probably 110F+). Coolant ran 200 to 201F and oil ran about 235F.
Next mod will be a LGM radiator (with internal oil and trans cooler) or a Z06 oil cooler with factory lines.
Next mod will be a LGM radiator (with internal oil and trans cooler) or a Z06 oil cooler with factory lines.
Melting Slicks
Joined: Sep 2005
Posts: 2,670
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From: merritt island fl
C1 of Year Finalist (stock) 2019
2016 C1 of the Year Finalist
2015 C2 of the Year Finalist
Drove from Dallas to Houston this week (LS3). Average speed was about 75 mph for three hours and the ambient temperature was near 100F (road surface was probably 110F+). Coolant ran 200 to 201F and oil ran about 235F.
Next mod will be a LGM radiator (with internal oil and trans cooler) or a Z06 oil cooler with factory lines.
Next mod will be a LGM radiator (with internal oil and trans cooler) or a Z06 oil cooler with factory lines.
Decreased MPG=engine working harder=more heat
Instructor
Joined: Oct 2000
Posts: 118
Likes: 0
From: Austin Texas
But this doesn't explain to me the differences between oil and coolant temps as I mentioned in the post. I am thinking that oil temp generally runs higher and the heat is transferred to the coolant/antifreeze to be dissipated by the radiator. Pardon my novice but I am not an expert in this area. Can you elaborate on this?
I just got my '08 Z51 and on the HUD I have the oil temp page up and it shows the oil temp (once I am warmed up and cruising on the interstate) 1 bar below the top. I would think it should be in the middle like tdelena's pic. I will click the DIC to see what temp is is reading out and compare with your posts.
My coolent seems to be fine on the gauges, but I will also check that on the DIC readout.
Drifting
Joined: Feb 2007
Posts: 1,844
Likes: 12
From: Alpharetta Georgia
Stop and go traffic in 102deg, 88% humidity weather yielded a max coolant temp of 210deg. This was with the A/C on. Most of the time it was at 207deg and just peaked at 210 for a minute or 2. On the highway the car ran 185deg on average. Temp was a cooler 98deg during this period though. I have a UD Pulley, a 160-t stat, and a Vengeance Racing tune with reprogrammed fans. I also remixed my coolant system to a 70/30 water/coolant ratio.