[Z06] C5 Z06 cooling issues
Thread Starter
Instructor
Joined: Dec 2007
Posts: 109
Likes: 0
C5 Z06 cooling issues
I have a 2004 C5 Z06 that I track quite a bit. Lately I was getting "transmission overheating" wornings so I installed a T1 Chevy factory transmission cooling system. No more transmission overheating now but the engine is running hot. Last time I was a the track it was hot, 100 degreesF and the engine was running around 240 degreesF. The little transmission radiator sits in front of the main radiator and prevents the air from getting to almost 1/3 of the radiator. Have you had this type of issue and how did you address it?
Racer
Joined: Sep 2008
Posts: 303
Likes: 1
I have a 2004 C5 Z06 that I track quite a bit. Lately I was getting "transmission overheating" wornings so I installed a T1 Chevy factory transmission cooling system. No more transmission overheating now but the engine is running hot. Last time I was a the track it was hot, 100 degreesF and the engine was running around 240 degreesF. The little transmission radiator sits in front of the main radiator and prevents the air from getting to almost 1/3 of the radiator. Have you had this type of issue and how did you address it?
Former Vendor
Joined: Feb 2004
Posts: 9,615
Likes: 13
From: Burlington NC
You can try to clean out the radiator and AC condenser. These cars pick up a ton of crap.
Or I would suggest this setup.
http://dougrippie.com/products/ron-d...-and-line-kit/
160 degree stat and fan reprogram doesn't really do much on the track.
Randy
Or I would suggest this setup.
http://dougrippie.com/products/ron-d...-and-line-kit/
160 degree stat and fan reprogram doesn't really do much on the track.
Randy
Instructor
Joined: Jun 2012
Posts: 211
Likes: 6
From: Corvette Owner since 1971 - 2004 Z06 Florida
I track my 2004 Z06 and had a similar issue after I put in the oil cooler. I solved it by putting the radiator fans on a toggle switch under the dash, so when I'm at the track the fans are on 100% of the time. It's an easy fix if you know someone good with the electrics.
Pro
Joined: Jul 2011
Posts: 608
Likes: 17
From: South Lyon, MI
I beg to differ there...lower t-stat temp means opening a lot earlier and constantly circulating the coolant and the fans will be constantly running and pulling hot air from the radiator...I don't see how that doesn't help, especially if you are auto-x and you are not able to get much air flow due to lower speeds.
Former Vendor
Joined: Feb 2004
Posts: 9,615
Likes: 13
From: Burlington NC
Ok, I do agree with the 160 t-stat to give it a head start. And to keep it from bouncing back and forth.
The fan thing, well most race cars and such run small fans for pit stops and in the paddock. I guess it would be track dependent, low speed tracks, auto-x, sure crank that baby up. Most road racing tracks in the US are fast enough where a fan will slow down air flow.
240 to 200 degrees is a big jump. I wonder what the oil temps were like at that water temp
Randy
The fan thing, well most race cars and such run small fans for pit stops and in the paddock. I guess it would be track dependent, low speed tracks, auto-x, sure crank that baby up. Most road racing tracks in the US are fast enough where a fan will slow down air flow.
240 to 200 degrees is a big jump. I wonder what the oil temps were like at that water temp
Randy
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Thread Starter
Instructor
Joined: Dec 2007
Posts: 109
Likes: 0
Ok, I do agree with the 160 t-stat to give it a head start. And to keep it from bouncing back and forth.
The fan thing, well most race cars and such run small fans for pit stops and in the paddock. I guess it would be track dependent, low speed tracks, auto-x, sure crank that baby up. Most road racing tracks in the US are fast enough where a fan will slow down air flow.
240 to 200 degrees is a big jump. I wonder what the oil temps were like at that water temp
Randy
The fan thing, well most race cars and such run small fans for pit stops and in the paddock. I guess it would be track dependent, low speed tracks, auto-x, sure crank that baby up. Most road racing tracks in the US are fast enough where a fan will slow down air flow.
240 to 200 degrees is a big jump. I wonder what the oil temps were like at that water temp
Randy
Former Vendor
Joined: Feb 2004
Posts: 9,615
Likes: 13
From: Burlington NC
I didn't look at the oil temp but I have a low temp thermostat and cleaning the radiator worked before I put the tranny cooler but now I have a debris screen. I just don't think the radiator gets enough air because of the little one sitting in front of it. I track the cqar at Laguna Seca, Sonoma and Thunderhill so we're talking 20 minutes of hard driving at a time. I'm thinking about changing the radiator with a DeWitt racing with double capacity. I still use the car on weekends so I don't want to take out the AC.
Being in that area you almost have to have a bigger radiator. Dry-hot and lots of 3rd gear.
Send me your email and I will get you some install instructions to help explain the system
Randy
Race Director
Joined: Aug 2004
Posts: 14,639
Likes: 39
From: Winston-Salem North Carolina
St. Jude Donor '08-'09
I was tracking at WGI one year and temps were in the high 90's and hit a high of 102. Oil temps were 300-305, coolant 240ish. I put in a DeWitts combo radiator oil cooler and oil temps haven't gone over 285, coolant 220 ish.
Thread Starter
Instructor
Joined: Dec 2007
Posts: 109
Likes: 0
Ok, I do agree with the 160 t-stat to give it a head start. And to keep it from bouncing back and forth.
The fan thing, well most race cars and such run small fans for pit stops and in the paddock. I guess it would be track dependent, low speed tracks, auto-x, sure crank that baby up. Most road racing tracks in the US are fast enough where a fan will slow down air flow.
240 to 200 degrees is a big jump. I wonder what the oil temps were like at that water temp
Randy
The fan thing, well most race cars and such run small fans for pit stops and in the paddock. I guess it would be track dependent, low speed tracks, auto-x, sure crank that baby up. Most road racing tracks in the US are fast enough where a fan will slow down air flow.
240 to 200 degrees is a big jump. I wonder what the oil temps were like at that water temp
Randy
Former Vendor
Joined: Feb 2004
Posts: 9,615
Likes: 13
From: Burlington NC
thank you for your help! You had me at 3rd gear. 😄 You have to know these tracks to know that. michael_chiorean@agilent.com
The elevation changes are hard on temps. That dry air doesn't cool at all, but is better for the driver.
Randy
Team Owner
Joined: Aug 2006
Posts: 30,897
Likes: 45
From: Picking on the weakest kid in the yard.
I beg to differ there...lower t-stat temp means opening a lot earlier and constantly circulating the coolant and the fans will be constantly running and pulling hot air from the radiator...I don't see how that doesn't help, especially if you are auto-x and you are not able to get much air flow due to lower speeds.
It doesn't help because if the coolant temp is at 240 degrees, the thermostat has been open and the fans have been on high since 230 degrees either way. If its going to climb above 230, its going to do it no matter what thermostat and fan setting you have.
DON"T Take out the AC. It's really not needed. Ron Davis and Dewitts both have the clips out front to mount the condenser. Between the two radiators you will find it like the Coke vs Pepsi. Both give positive results. We have been running the Ron Davis radiators for a really long time. I suggested the model with a EOC, because I'm 100 certain that your oil temps are 300ish, and it would be a good time to knock that down.
Being in that area you almost have to have a bigger radiator. Dry-hot and lots of 3rd gear.
Send me your email and I will get you some install instructions to help explain the system
Randy
Being in that area you almost have to have a bigger radiator. Dry-hot and lots of 3rd gear.
Send me your email and I will get you some install instructions to help explain the system
Randy
I had the same problem with overheated coolant and oil. Ron Davis with integrated oil cooler soundly solved both problems permanently. Excellent mod.
Race Director
Joined: Jan 2008
Posts: 16,028
Likes: 170
From: oregon
I beg to differ there...lower t-stat temp means opening a lot earlier and constantly circulating the coolant and the fans will be constantly running and pulling hot air from the radiator...I don't see how that doesn't help, especially if you are auto-x and you are not able to get much air flow due to lower speeds.
autocross maybe, as it could help keep you cooler during staging
Safety Car
Joined: Jan 2012
Posts: 3,956
Likes: 520
From: Da U.P.
95 degrees and dry up here in CO, my Z06 with stock radiator (clean), ~30% coolant/water wetter, and EOC would get the coolant around 235 just in HPDE for a 20 minute session. Oil around 275. Only way to lower it is to open the wallet for a radiator AND oil cooler. There's a guy running TT here in a C5Z with a Dewitts radiator and no oil cooler, his coolant runs in the 21X range and oil still passes 300 degrees. He ponies up for Amsoil, but that's just too damn hot for my liking. Thermostat would be a waste of time, it's good for racing where you might need the extra power for the first couple laps, but by the end of the session you'll end up right at the same temperature anyway. Like Randy said, all it does is give your coolant system a "head start".
Advanced
Joined: Jul 2011
Posts: 66
Likes: 1
From: Big Bear City CA
I have a 2004 C5 Z06 that I track quite a bit. Lately I was getting "transmission overheating" wornings so I installed a T1 Chevy factory transmission cooling system. No more transmission overheating now but the engine is running hot. Last time I was a the track it was hot, 100 degreesF and the engine was running around 240 degreesF. The little transmission radiator sits in front of the main radiator and prevents the air from getting to almost 1/3 of the radiator. Have you had this type of issue and how did you address it?
It still gets warm on the track....136 day before yesterday at willow springs but when you are putting out 650hp from a cooling system designed for 400....i just left it in 4th more instead of winding out 3rd to redline so much and the temps would plummet.
Advanced
Joined: Jul 2011
Posts: 66
Likes: 1
From: Big Bear City CA
I have a 2004 C5 Z06 that I track quite a bit. Lately I was getting "transmission overheating" wornings so I installed a T1 Chevy factory transmission cooling system. No more transmission overheating now but the engine is running hot. Last time I was a the track it was hot, 100 degreesF and the engine was running around 240 degreesF. The little transmission radiator sits in front of the main radiator and prevents the air from getting to almost 1/3 of the radiator. Have you had this type of issue and how did you address it?